Article

Association of Single Nucleotide Polymorphism rs6903956 on Chromosome 6p24.1 with Coronary Artery Disease and lipid levels in different ethnic groups of the Singaporean Population.

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Abstract

Objective: A recent genome wide association study in the Chinese population has implicated rs6903956 within the ADTRP gene on chromosome 6p24.1 as a novel susceptibility locus for coronary artery disease (CAD). In this study, we evaluated the association of rs6903956 with CAD in the different ethnic groups of Singaporean population comprising Chinese, Malays and Asian Indians. Design and methods: The genotypes of the rs6903956 SNP were determined in 645 CAD patients and 755 control group Singaporean subjects by using the polymerase chain reaction restriction fragment length polymorphism method (PCR-RFLP). We then tested the association of this SNP with CAD and lipid profiles. Results: The risk allele A of rs6903956 was associated significantly only in the Chinese with an odds ratio (OR) of 2.03 (95% CI 1.04-3.96, P=0.037) when analyzed by each ethnic group separately. In a meta-analysis with pooled subjects from all three ethnic groups, rs6903956 showed highly significant association with CAD both before (observed P=1.39e-04; OR=1.66; 95% CI 1.28-2.15) and after adjustment (P=4.63e-03; OR=1.86; 95% CI 1.21-2.87) for conventional risk factors of age, gender, BMI, smoking status and ethnicity. No significant association was observed between rs6903956 genotypes and lipid profiles in Chinese, Malays and Indians, suggesting that the association of this SNP with CAD is not mediated through plasma lipids. Conclusion: The SNP rs6903956 within the ADTRP gene on chromosome 6p24.1 is significantly associated with CAD in different ethnic groups of the Singaporean population.

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... The novel C6orf105 protein was found to regulate TFPI expression in endothelial cells in an androgen-dependent manner, and it was thus termed androgen-dependent TFPIregulating protein (ADTRP) [7]. Since the identification of ADTRP, there have been several studies associating singlenucleotide polymorphisms (SNPs) in the ADTRP gene with cardiovascular diseases [8][9][10][11], as well as research providing mechanistic insights on this novel protein and its functional role [7,12,13]. In this review, we aim to summarize the current literature on ADTRP, with a focus on the peripheral actions of ADTRP, including expression, genetic variations, signaling pathways, and function. ...
... and among the different ethnic groups (Chinese, Malay, and Indian) of the Singaporean population (OR = 1.86, 95%CI: 1.21-2.87) [10]. However, we did not find significant association between rs6903956 and plasma lipids, factor VII coagulant activity (FVIIc), and fibrinogen levels, suggesting that the association between rs6903956 and CAD may not be mediated through plasma lipids, FVIIc, and fibrinogen [10,24]. ...
... [10]. However, we did not find significant association between rs6903956 and plasma lipids, factor VII coagulant activity (FVIIc), and fibrinogen levels, suggesting that the association between rs6903956 and CAD may not be mediated through plasma lipids, FVIIc, and fibrinogen [10,24]. ...
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The first genome-wide association study on coronary artery disease (CAD) in the Han Chinese population identified C6orf105 as a susceptibility gene. The C6orf105 gene was later found to encode for a protein that regulates tissue factor pathway inhibitor (TFPI) expression in endothelial cells in an androgen-dependent manner, and the novel protein was thus termed androgen-dependent TFPI-regulating protein (ADTRP). Since the identification of ADTRP, there have been several studies associating genetic variants on the ADTRP gene with CAD risk, as well as research providing mechanistic insights on this novel protein and its functional role. ADTRP is a membrane protein, whose expression is upregulated by androgen, GATA-binding protein 2, oxidized low-density lipoprotein, peroxisome proliferator‐activated receptors, and low-density lipoprotein receptors. ADTRP regulates multiple downstream targets involved in coagulation, inflammation, endothelial function, and vascular integrity. In addition, ADTRP functions as a fatty acid esters of hydroxy fatty acid (FAHFA)-specific hydrolase that is involved in energy metabolism. Current evidence suggests that ADTRP may play a role in the pathogenesis of atherosclerosis, CAD, obesity, and metabolic disorders. This review summarizes the current literature on ADTRP, with a focus on the peripheral actions of ADTRP, including expression, genetic variations, signaling pathways, and function. The evidence linking ADTRP and cardiometabolic diseases will also be discussed.
... Previously, the association between rs6903956 within the first intron of ADTRP and risk for CAD was replicated in our Singaporean Chinese population [16]. The study also found that the association was not mediated through plasma lipid levels. ...
... The DNA sequence of the ADTRP was obtained from National Center for Biotechnology Information (NCBI) dbSNP database (build 37). Detailed information regarding the primer design, optimization, condition of amplification reactions, PCR products digestion, incubation conditions for RFLP and confirmation of the genotyping results was described elsewhere [16]. The presence of 2 DNA fragments with the length of 378 and 31 bp respectively indicated the presence of the minor risk A allele while a single band of 409 bp indicated the presence of the major G allele. ...
... It is suggested that a decreased expression of ADTRP may lead to a reduction in TFPI expression and thus result in an increased risk for atherosclerosis and CAD. The association between rs6903956 and CAD risk has been replicated in independent Chinese cohorts [16,30]. This single nucleotide polymorphism (SNP) was also reported to be associated with CAD in the Japanese, although the risk allele in their population was G and hence different from the Chinese [31]. ...
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Background Genome-wide association study (GWAS) has reported that rs6903956 within the first intron of androgen-dependent tissue factor pathway inhibitor (TFPI) regulating protein (ADTRP) gene is associated with coronary artery disease (CAD) risk in the Chinese population. Although ADTRP is believed to be involved in the upregulation of TFPI, the underlying mechanism involved is largely unknown. This study investigated the association of rs6903956 with plasma Factor VII coagulant activity (FVIIc) and fibrinogen levels, which are regulated by TFPI and are independent risk predictors for CAD. Methods We conducted the analysis in both Chinese adult (N = 309) and neonatal cohorts (N = 447). The genotypes of the rs6903956 single nucleotide polymorphism (SNP) were determined by the polymerase chain reaction restriction fragment length polymorphism method (PCR–RFLP). FVIIc and fibrinogen level were measured from citrated plasma. The association between rs6903956 and coagulation factors was tested by linear regression with adjustment for possible confounders. Analysis was carried out in adults and neonates separately. Results No significant association was observed between rs6903956 and plasma FVIIc nor fibrinogen levels with adjustment for age, gender, body mass index (BMI) and cigarette smoking in adults (P for FVIIc = 0.464; P for fibrinogen = 0.349). The SNP was also not associated with these two coagulation factors in the neonates (P for FVIIc = 0.579; P for fibrinogen = 0.359) after adjusting for gestational age, gender and birth weight. Conclusions SNP rs6903956 on ADTRP gene was not associated with plasma FVIIc nor fibrinogen levels.
... In 2013, A Singapore GWAS study on various ethnic groups (including Chinese, Malays and Indians) found SNP rs6903956 of the ADTRP gene located on chromosome 6p24.1 is associated with CHD. [5] In 2014, a research on the relationship between CDKN2A/B, ADTRP and PDGFD gene polymorphism and CHD in the Japanese population showed that ADTRP was an important risk factor for CHD but the risk alleles in the Japanese population and Chinese population are different. [6] The genetic law shows that the genetic factor plays an important role in the development of CAD. ...
... Therefore, inferring that rs6903956 may affect the risk of CHD by influencing the expression of c6orf105 mRNA, ADTRP is considered to be the protective factor of CAD. [5] The ADTRP gene was first identified to be in association with CHD in the Chinese Han population and was further confirmed in the Han population in Singapore and the Japanese population. [5,6] However, the study of the above two groups of population have been focused on rs6903956. ...
... [5] The ADTRP gene was first identified to be in association with CHD in the Chinese Han population and was further confirmed in the Han population in Singapore and the Japanese population. [5,6] However, the study of the above two groups of population have been focused on rs6903956. No new generic loci associated with CAD have been located. ...
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Objectives: To study the association of single nucleotide polymorphism (SNP) rs2076185 in chromosome 6p24.1 with the premature coronary artery diseases (PCAD) in Chinese Han population. Methods: A total of 1382 patients were divided into the PCAD group and the control group based on their coronary arteriography (CAG) results. Their SNP rs2076185 were analyzed by the mass-spectrometry. Their allele and genotype frequency in Hardy-Weinberg equilibrium were calculated for assessment. Logistic regression was employed to remove confounding factors and correlate SNP rs2076185 with PCAD. Results: The allele and genotype frequencies of the control group were in Hardy-Weinberg equilibrium (P > 0.05). The frequencies of allele G of rs2076185 were 54.2% in the PCAD group and 49.5% in the control group. The difference was significant (P = 0.042). The genotype distribution of rs2076185 of the two groups was also significantly different. The univariate analysis showed that the rs2076185 polymorphisms were associated with the PCAD only in the additive model (OR: 0.828, 95% CI: 0.711-0.964, P = 0.014), and in the dominant model (OR: 0.753, 95% CI: 0.591-0.958, P = 0.021). After removing the confounding variables, the rs2076185 polymorphisms was associated with PCAD in the additive model (OR: 0.775, 95% CI: 0.648-0.928, P = 0.005), in the dominant model (OR: 0.698, 95% CI: 0.527-0.925, P = 0.012), and in the recessive model (OR: 0.804, 95% CI: 0.538-0.983, P = 0.038). Conclusion: Allele G of rs2076185 reduces the PCAD risks in Chinese Han population, therefore it could be a coronary artery diseases protective factor in Chinese Han population.
... A recent GWAS in a Chinese population identified rs6903956, which lies within intron 1 of the androgen-dependent tissue factor pathway inhibitor regulating protein (ADTRP) gene on chromosome 6p24.1, as a novel susceptibility locus for CAD 2,5,6) . At chromosome 11q22.3, ...
... The results showed CDKN2A/B (rs1333049) to be the most robust SNP, exhibiting a significant association sians based on GWAS examinations 20) . Although ADTRP was first identified in a Han Chinese population and later replicated in two small Han Chinese cohorts, a recent large GWAS in a Han Chinese population failed to identify whether this gene is a causative susceptibility locus 2,5,6,21) . Although rs6903956 has also been evaluated in the same racial group, the results are controversial. ...
... Therefore, a decreased expression of ADTRP may be a pathogenic cause of CAD 2) . Interestingly, we found ADTRP to be a significant coronary risk factor, although this risk allele differs between Han Chinese and Japanese populations 2,5) . As a minor allele, its frequency is low in Japanese subjects; therefore, we performed direct sequencing, which confirmed our genotyping findings. ...
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Aim: Genome-wide association studies have identified a series of susceptibility loci for coronary artery disease(CAD). The present study attempted to replicate the results for eight of these loci, CDKN2A/B(rs1333049), ADTRP(rs6903956), PDGFD(rs974819), TCF21(rs12190287), COL4A1-A2(rs4773144), HHIPL1(rs2895811), ADAMTS7(rs4380028) and UBE2Z(rs46522), in patients with pathologically defined atherosclerosis of the coronary arteries. Methods: Autopsy cases of elderly Japanese subjects were enrolled in the JG-SNP study(n=1,536). Polymorphisms were genotyped, and their associations with the coronary stenosis index(CSI) and incidence of pathological myocardial infraction(MI) were investigated. The potential combinatorial effects of the susceptibility loci were also assessed. Results: Among the eight loci tested, three exhibited signs of positive associations. CDKN2A/B showed the most robust associations with CSI and MI(p=0.007 and OR=1.843, 95% CI 1.293-2.629, p=0.001, for CC+CG vs. GG). In addition, ADTRP demonstrated associations with CSI and MI, although the risk allele was opposite from that observed in the original report(p=0.008 and OR=1.652, 95% CI 1.027-2.656, p=0.038 for GG vs. AA+AG). Meanwhile, PDGFD displayed a suggestive association with CSI in women, but not men(p=0.023). CDKN2A/B and ADTRP were also found to be significantly associated with the severity of the CSI in a case-control setting. The cumulative risk allele counting of CDKN2A/B, ADTRP and PDGFD indicated an increased number of risk alleles to be associated with a higher CSI(p=4.61E-05). Conclusions: The present study confirmed the association between CDKN2A/B and CAD and identified a different associated risk allele of ADTRP. PDGFD was found to exhibit a gender-specific association with CAD. The combination of multiple risk alleles may be associated with a higher risk of CAD.
... Chunyan Luo, Bo Tang and Subo Qin authors made an equal contribution to this work. groups (Guo et al. 2012;Tayebi et al. 2013;Huang et al. 2015). ADTRP co-localizes with CAV1 in the caveolae of endothelial cells (ECs) and upregulates tissue factor pathway inhibitor (TFPI) protein (Lupu et al. 2011), which is known to inhibit the anticoagulant factor Xa (FXa) and increase thrombosis (Lupu et al. 2011). ...
... In a previous GWAS (Wang et al. 2011), SNP rs6903956 mapping to chromosome 6p24.1 was found to have a notable association with CAD in the Chinese Han population. This correlation was validated by several independent follow-up studies (Guo et al. 2012;Tayebi et al. 2013;Huang et al. 2015). Rs6903956, located in ADTRP intron 1 is significantly correlated with its transcription in lymphocytes. ...
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Myocardial infarction (MI) is a frequent outcome of coronary artery disease (CAD) and the key factor contributing to worldwide disability and death. Genetic factors contribute to the pathogenesis of CAD/MI, and SNP rs6903956 in the ADTRP gene was first found associated with CAD/MI in the Chinese Han population, which was successfully replicated in other cohorts. However, whether rs6903956 is a functional SNP and its risk mechanism to CAD/MI remains unknown. The ADTRP gene-encoded androgen-dependent TFPI regulating protein regulates vascular endothelial cell function, endothelial–monocyte adhesion, and thrombosis. The allele A of rs6903956, in particular, is associated with lower ADTRP mRNA levels in lymphocytes. In the current study, we found that SNP rs6903956 exhibits allelic differences in transcriptional activity by interacting with GATA2. Also, the A allele conferred a greater risk of CAD and MI, lowered transcriptional activity, and GATA2 binding ability as compared to the G allele. Our findings provide details on how rs6903956 regulates the expression of ADTRP and may provide novel insights into CAD pathology and susceptibility.
... The first GWAS for CAD and MI in a non-Caucasian population identified a genomic variant in the C6orf105 gene that showed highly significant association with CAD and MI . The finding was confirmed by several independent follow-up studies (Guo et al., 2012;Tayebi et al., 2013;Dechamethakun et al., 2014;Huang et al., 2015;Nelson et al., 2017). Later, C6orf105 was shown to be highly expressed in endothelial cells (ECs), co-localized with TFPI (Tissue Factor Pathway Inhibitor, a key inhibitor of coagulation) and caveolin-1 in ECs, and regulated the expression level of TFPI in ECs (Lupu et al., 2011). ...
... Genomic variants in ADTRP and TFPI were reported to be significantly associated with risk of CAD and MI Guo et al., 2012;Tayebi et al., 2013;Dechamethakun et al., 2014;Huang et al., 2015;Nelson et al., 2017;Zhao et al., 2017;Naji et al., 2018). Therefore, we hypothesized that genomic variants in POU1F1 were also associated with risk of CAD. ...
... According to the World Health Organization, it is predicted that 23.6 million deaths per year will be because of cardiovascular diseases by 2030 [3]. CAD, with a complex etiology, is considered to be the result of an interaction between genetic and environmental factors [4][5][6]. In the past decades, many contributing factors including smoking, hypertension, diabetes mellitus (DM), atherosclerosis, obesity, and diet have been established, but the exact etiology underlying CAD remains obscure. ...
... A limitation of the present study is that the control population differs from the cases, in terms of age and cardiovascular risk factors. The mean age difference (~5 years) should be acceptable in an epidemiologic study of CAD according to a previous report [6,9]. CAD predominates in an older population. ...
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Coronary artery disease (CAD) is one of the most common diseases leading to mortality and morbidity worldwide. There is considerable debate on whether serum transforming growth factor beta1 (TGF-beta1) levels are associated with long-term major adverse cardiovascular events in patients with CAD, and to date, no study has specifically addressed levels in patients with different degrees of CAD severity. Serum TGF-beta1 and mothers against decapentaplegic homolog 3 (SMAD3) concentrations were evaluated in 279 patients with CAD and 268 controls without CAD. The clinical and biochemical characteristics of all subjects were also determined and analyzed. TGF-beta1 and SMAD3 concentrations in CAD patients were significantly higher than those in the controls. The serum TGF-beta1 level in acute myocardial infarction (AMI) was significantly higher than that in both stable angina pectoris (SAP) and unstable angina pectoris (UAP) (p < 0.05), while there was no marked difference between levels in SAP and UAP (p > 0.05). SMAD3 levels showed no obvious difference among AMI, SAP, and UAP. TGF-beta1 and SMAD3 are potential biomarkers for CAD, and may be more accurate than Lpa, ApoA1, uric acid, BUN, or triglycerides (TG). Serum TGF-beta1 and SMAD3 levels are closely associated with CAD, and may become useful biomarkers for diagnosis and risk stratification.
... In the first genetic analysis of coronary artery disease in the Chinese Han population, we used the GeneID database for the first time to find a single nucleotide polymorphism (genomic variation) SNP rs6903956 in intron 1 of the C6orf105 gene (now known as ADTRP), which significantly increased the risk of CAD and MI, and was associated with decreased expression of ADTRP [25]. Other groups also replicate this association [26][27][28][29]. ...
Article
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Coronary artery disease (CAD) and its main complication, myocardial infarction (MI), is a complex disease caused by environmental and genetic factors and their interaction. Family-based linkage analysis and genome-wide association studies have indicated many of genetic variations related to CAD and MI in recent years. Some are in the coding sequence, which mediates the coding protein, while others are in the non-coding region, which affects the expression of adjacent genes and forms differential gene expression. These variants and differential expressions will have varying degrees of impact on the development of the cardiovascular system and normal heart electrical activity function, subsequently leading to CAD and MI. Among these affected genes, some Transcription Factors (TFs), as important means of transcriptional regulation, have a key role in the pathogenesis of coronary artery disease and myocardial infarction. The GATAs binding protein 2 (GATA2) enhances monocyte adhesion and promoted vessel wall permeabilization through vascular EC adhesion molecule 1 (VCAM-1) upregulation, further revealing its atherosclerosis-promoting role. Myocyte enhancer factor 2 (MEF2) has a role in fostering many functions of the atherosclerotic endothelium and is a potential therapeutic target for atherosclerosis, thrombosis, and inflammation. Nuclear factor-kappa B (NF-κB) is an important promoter of vascular endothelial growth factor (VEGF)-driven angiogenesis, and its pathway has a key role in atherosclerosis-related complications such as angiogenesis, inflammation, apoptosis, and immune effects. Activating transcription factor 3 (ATF3) may be a novel prognostic biomarker and therapeutic target for atherosclerosis. The important role of signal transducer and activator of transcription 3 (STAT3) (especially in mitochondria) in endothelial cells (EC) dysfunction, inflammation, macrophage polarization and immunity in atherosclerosis.
... SNP rs6903956 associates with decreased expression of ADTRP, which could be partially responsible for pathogenesis in CAD/MI. SNP rs6903956 within the ADTRP gene is also significantly associated with CAD in ethnic groups in Singapore independently of conventional risk factors [49]. ...
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The novel protein ADTRP, identified and described by us in 2011, is androgen-inducible and regulates the expression and activity of Tissue Factor Pathway Inhibitor, the major inhibitor of the Tissue Factor-dependent pathway of coagulation on endothelial cells. Single-nucleotide polymorphisms in ADTRP associate with coronary artery disease and myocardial infarction, and deep vein thrombosis/venous thromboembolism. Some athero-protective effects of androgen could exert through up-regulation of ADTRP expression. We discovered a critical role of ADTRP in vascular development and vessel integrity and function, manifested through Wnt signaling-dependent regulation of matrix metalloproteinase-9. ADTRP also hydrolyses fatty acid esters of hydroxy-fatty acids, which have anti-diabetic and anti-inflammatory effects and can control metabolic disorders. Here we summarize and analyze the knowledge on ADTRP and try to decipher its functions in health and disease.
... In addition, its risk allele A was associated with decreased ADTRP mRNA expression, suggesting that low level of ADTRP may confer increased CAD susceptibility [8]. Our group has validated the finding by Wang et al. [8] and found that rs6903956 was also associated with higher CAD risk in our Singaporean Chinese Han population [9]. ...
Article
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Androgen dependent tissue factor pathway inhibitor regulating protein (ADTRP) is a novel protein associated with coronary artery disease (CAD) susceptibility, and reduced mRNA expression of ADTRP was shown to be associated with increased CAD risk. This study aimed to determine and compare circulating ADTRP levels between CAD patients and controls, and to test the performance of plasma ADTRP as a biomarker for CAD. We measured plasma ADTRP, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and high sensitivity-C reactive protein (hs-CRP) levels in 362 CAD patients, 150 angiographically negative CAD controls, and 83 healthy adults with no known clinical or medical conditions using commercial ELISA. Statistical analyses were performed using receiver operator characteristic (ROC) curves, quantile regression and logistic regression, with adjustments for age, gender, ethnicity and BMI. CAD patients had significantly lower plasma ADTRP levels 1,545 (1,087–2,408) pg/ml as compared to CAD controls 2,259 (1,533–3,778) pg/ml and healthy adults 3,904 (2,732–5,463) pg/ml. Plasma ADTRP outperformed the other three inflammatory biomarkers (TNF-α, IL-6 and hs-CRP) for CAD (Area under ROC curve: 0.67, Odds ratio (OR): 0.907). Our study has shown for the first time that ADTRP is present in circulation, and that plasma ADTRP may be a novel independent biomarker for CAD.
... pylori) have also been analyzed. Tayebi et al. (2013) focused on coronary artery disease and lipid levels among the population in Singapore and the comparison among three major ethnics was made. Furthermore, Wong et al. (2013) and Cheng et al. (2014) reviewed the sequencing of hundred Malay ethnics of South Asia and Oceania through the Singapore Sequencing Malay Project (SSMP) using the SNPs marker to complete the 1000 Genomes Project (1KGP). ...
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Malays are a distinctive nation native as well as among the oldest ethnic group in the world encompassing the land of Nusantara, Madagascar and the Pacific Islands. The Malay civilization is associated with the Southeast Asian region known as the Malay Archipelago, the Malay-Indonesian Archipelago, the Nusantara, the Malay Realm and the Land of Java. It also includes the islands of Indonesia, Malaya, the islands of Borneo, Philippines, Singapore which consisting two communities namely Proto-Malay (aboriginal Malay) and Deutero-Malay (new Malay). Therefore, this study attempts to shed some light on the origins of the Malay community from the historical point of view and its relation to modern genomic field. The findings indicate that there is a significant relationship between the history of Malay origins and the modern genomic field that was done through the mitochondrial DNA analysis. This is followed by the Nusantara that serves as the major genetic reservoir of the world Malay group. Thus, it is apparent that the genomic study of the Malay ethnic group is not solely focused on the origins of the nation alone, but to enhance the health level of the race through disease analyses, medical practice and research. Subsequently, this will lead to the production of pharmaceutical products which is indeed beneficial in addressing local health needs.
... 1,3 Genome-wide association studies revealed that single-nucleotide polymorphisms in ADTRP associate with deep vein thrombosis/venous thromboembolism, 4 myocardial infarction, 5 and coronary artery disease, possibly through regulation of melanoma inhibitory activity protein 3 (MIA3)/transport and Golgi organization protein 1 (TANGO1), collagen VII, and apolipoprotein B (ApoB). 6,7 A novel function was recently discovered for ADTRP and androgen-inducible gene 1, namely that they could hydrolyze bioactive fatty acid esters of hydroxy-fatty acids in vitro 8 ; however, the in vivo significance of this finding is elusive. ...
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Background The physiological function of ADTRP (androgen‐dependent tissue factor pathway inhibitor regulating protein) is unknown. We previously identified ADTRP as coregulating with and supporting the anticoagulant activity of tissue factor pathway inhibitor in endothelial cells in vitro. Here, we studied the role of ADTRP in vivo, specifically related to vascular development, stability, and function. Methods and Results Genetic inhibition of Adtrp produced vascular malformations in the low‐pressure vasculature of zebrafish embryos and newborn mice: dilation/tortuosity, perivascular inflammation, extravascular proteolysis, increased permeability, and microhemorrhages, which produced partially penetrant lethality. Vascular leakiness correlated with decreased endothelial cell junction components VE‐cadherin and claudin‐5. Changes in hemostasis in young adults comprised modest decrease of tissue factor pathway inhibitor antigen and activity and increased tail bleeding time and volume. Cell‐based reporter assays revealed that ADTRP negatively regulates canonical Wnt signaling, affecting membrane events downstream of low‐density lipoprotein receptor‐related protein 6 (LRP6) and upstream of glycogen synthase kinase 3 beta. ADTRP deficiency increased aberrant/ectopic Wnt/β‐catenin signaling in vivo in newborn mice and zebrafish embryos, and upregulated matrix metallopeptidase (MMP)‐9 in endothelial cells and mast cells (MCs). Vascular lesions in newborn Adtrp−/− pups displayed accumulation of MCs, decreased extracellular matrix content, and deficient perivascular cell coverage. Wnt‐pathway inhibition reversed the increased mmp9 in zebrafish embryos, demonstrating that mmp9 expression induced by Adtrp deficiency was downstream of canonical Wnt signaling. Conclusions Our studies demonstrate that ADTRP plays a major role in vascular development and function, most likely through expression in endothelial cells and/or perivascular cells of Wnt‐regulated genes that control vascular stability and integrity.
... We previously reported the first GWAS for CAD in the Chinese population and identified a SNP in the ADTRP gene (rs6903956) that reduces expression of ADTRP and increases risk of CAD and MI (Wang et al. 2011). The finding was replicated by multiple independent studies (Guo et al. 2012;Huang et al. 2015a;Tayebi et al. 2013). Lupu et al. (2011) showed that ADTRP regulated the TFPI expression level in endothelial cells. ...
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The tissue factor pathway inhibitor (TFPI) gene encodes a protease inhibitor with a critical role in regulation of blood coagulation. Some genomic variants in TFPI were previously associated with plasma TFPI levels, however, it remains to be further determined whether TFPI variants are associated with other coagulation factors. In this study, we carried out a large population-based study with 2313 study subjects for blood coagulation data, including fibrinogen levels, prothrombin time (PT), activated partial thromboplastin time (APTT), and thrombin time (TT). We identified significant association of TFPI variant rs10931292 (a functional promoter variant with reduced transactivation) with increased plasma fibrinogen levels (P = 0.017 under a recessive model), but not with PT, APTT or TT (P > 0.05). Using a large case–control association study population with 4479 CAD patients and 3628 controls, we identified significant association between rs10931292 and CAD under a recessive model (OR 1.23, P = 0.005). For the first time, we show that a TFPI variant is significantly associated with fibrinogen levels and risk of CAD. Our finding contributes significantly to the elucidation of the genetic basis and biological pathways responsible for fibrinogen levels and development of CAD.
... The first GWAS for CAD and MI in the Chinese population using the GeneID database identified an intronic single nucleotide polymorphism (SNP) rs6903956 in the C6orf105 gene (now referred to as ADTRP) that increases risk of CAD and MI and is associated with decreased expression of ADTRP [2]. The association was replicated by other groups [3][4][5][6]. ADTRP encodes an Androgen-Dependent TFPI-Regulating Protein, a cell surface protein with six transmembrane domains. The ADTRP protein was found to be co-localized with CAV1 in the caveolae on the cell surface and to positively regulate the expression of TFPI in endothelial cells (ECs), resulting in inhibition of FXa involved in coagulation and thrombosis [7]. ...
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Coronary artery disease (CAD) is the leading cause of death worldwide. GWAS have identified > 50 genomic loci for CAD, including ADTRP and MIA3/TANGO1. However, it is important to determine whether the GWAS genes form a molecular network. In this study, we have uncovered a novel molecular network between ADTRP and MIA3/TANGO1 for the pathogenesis of CAD. We showed that knockdown of ADTRP expression markedly down-regulated expression of MIA3/TANGO1. Mechanistically, ADTRP positively regulates expression of PIK3R3 encoding the regulatory subunit 3 of PI3K, which leads to activation of AKT, resulting in up-regulation of MIA3/TANGO1. Both ADTRP and MIA3/TANGO1 are involved in endothelial cell (EC) functions relevant to atherosclerosis. Knockdown of ADTRP expression by siRNA promoted oxidized-LDL-mediated monocyte adhesion to ECs and transendothelial migration of monocytes, inhibited EC proliferation and migration, and increased apoptosis, which was reversed by expression of constitutively active AKT1 and MIA3/TANGO1 overexpression, while the over-expression of ADTRP in ECs blunted these processes. Knockdown of MIA3/TANGO1 expression also promoted monocyte adhesion to ECs and transendothelial migration of monocytes, and vice versa for overexpression of MIA3/TANGO1. We found that ADTRP negatively regulates the levels of collagen VII and ApoB in HepG2 and endothelial cells, which are downstream regulatory targets of MIA3/TANGOI. In conclusion, we have uncovered a novel molecular signaling pathway for the pathogenesis of CAD, which involves a novel gene-gene regulatory network. We show that ADTRP positively regulates PIK3R3 expression, which leads to activation of AKT and up-regulation of MIA3/TANGO1, thereby regulating endothelial cell functions directly relevant to atherosclerosis.
... Our genome-wide association studies in the Chinese population identified a genomic variant, rs6903956, in intron 1 of the C6orf105 gene (later named as ADTRP) as a significant risk factor for CAD and MI (27). This finding was confirmed by multiple follow-up replication studies (11,17,19,25). The ADTRP gene encodes a 230 amino acid protein referred to as androgen-dependent TFPI-regulating protein because it regulates expression of tissue factor pathway inhibitor (TFPI) in endothelial cells and its expression can be induced by androgen (22). ...
Article
The ADTRP gene encodes the Androgen-Dependent TFPI-Regulating Protein and is a susceptibility gene for contrary artery disease (CAD). We performed global gene expression profiling for ADTRP knockdown using microarrays in human HepG2 cells. Follow-up real-time RT-PCR analysis demonstrated that ADTRP regulates a diverse set of genes, including up-regulation of 7 histone genes, down-regulation of multiple cell cycle genes (CCND1, CDK4 and CDKN1A), and up-regulation of apoptosis genes (CASP7 and PDCD2) in HepG2 cells and endothelial cells. Consistently, ADTRP increases the number of S phase cells during cell cycle, promotes cell proliferation and inhibits apoptosis. Our study provides novel insights into the function of ADTRP and biological pathways involving ADTRP, which may be involved in the pathogenesis of CAD.
... As we recently reported, a GWAS has revealed that rs6903956 in intron 1 of ADTRP on chromosome 6p24.1 was associated with CAD in a Han Chinese population [13]. The association was later replicated respectively in a Han Chinese cohort [15] and a Chinese ethnic Singaporean cohort [16]. Rs6903956 was also demonstrated to associate with the mRNA expression of ADTRP [13]. ...
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The first genome-wide association study for coronary artery disease (CAD) in the Han Chinese population, we reported recently, had identified rs6903956 in gene ADTRP on chromosome 6p24.1 as a novel susceptibility locus for CAD. The risk allele of rs6903956 was associated with decreased mRNA expression of ADTRP. To further study the correlation of ADTRP expression and CAD, in this study we evaluated the associations of eight common variants in the expression-regulating regions of ADTRP with CAD in the Southern Han Chinese population. Rs169790 in 3'UTR, rs2076189 in 5'UTR, four SNPs (rs2076188, rs7753407, rs11966356 and rs1018383) in promoter, and two SNPs (rs3734273, rs80355771) in the last intron of ADTRP were genotyped in 1716 CAD patients and 1572 controls. The correlations between these loci and total or early-onset CAD were investigated. None of these loci was discovered to associate with total CAD (P > 0.05). However, with early-onset CAD, significant both allelic and genotypic associations of rs7753407, rs11966356 and rs1018383 were identified, after adjustment for risk factors of age, gender, hypertension, diabetes, lipid profiles and smoking (adjusted P < 0.05). A haplotype AGCG (constructed by rs2076188, rs7753407, rs11966356 and rs1018383) was identified to protect subjects from early-onset CAD (OR = 0.332, 95% CI = 0.105-0.879, adjusted P = 0.010). Real-time quantitative reverse transcription polymerase chain reaction assay showed that the risk alleles of the associated loci were significantly associated with decreased expression of ADTRP mRNA. Moreover, the average level of ADTRP mRNA expression in early-onset CAD cases was significantly lower than that in controls. Our results provide new evidence supporting the association of ADTRP with the pathogenesis of early-onset CAD.
... In contrast to CDKN2A/B (rs10757274), we found that the genetic variant of ADTRP (rs6903956) on 6p24 was not associated with MI after adjusting for conventional confounding factors, which is inconsistent with recent research results reported in a Japanese population [37]. To our knowledge, only this solo Japanese research report has investigated the association between ADTRP (rs6903956) and MI to date, and the risk allele identified in this Japanese study differs from our study and two other studies conducted in Han Chinese and Japanese populations [14,38]. Most former studies have focused on the identification of associations between ADTRP and CAD, but the results are controversial even in the same racial population [14,39,40]. ...
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Myocardial infarction (MI) is a serious complication of Coronary Artery Disease (CAD). Previous studies have identified genetic variants on chromosome 9p21 and 6p24 that are associated with CAD, but further studies need to be conducted to investigate whether these genetic variants are associated with the pathogenesis of MI. We therefore performed this study to assess the association between the risk of MI and SNP rs10757274 on chromosome 9p21 and SNP rs6903956 on chromosome 6p24, and to explore the gene-environment interactions in a Chinese population. A hospital-based case-control study, consisting of 502 MI patients and 308 controls, was conducted in a Chinese population. Demographic, behavioral information and clinical characteristics were collected, and genotyping of the two SNPs was performed using single base primer extension genotyping technology. The unconditional logistic regression (ULR) method was adopted to assess the association of the two SNPs with MI risk. Both generalized multifactor dimensionality reduction (GMDR) and ULR methods were applied to explore the effect of gene-environment interactions on the risk of MI. After adjusting for covariates, it was observed that SNP rs10757274 on chromosome 9p21 was significantly associated with MI. Compared with subjects carrying the AA genotype, subjects carrying the GA or GG genotypes had a higher MI risk (ORa = 1.52, 95%CI:1.06-2.19, pa = 0.0227; ORa = 2.40, 95%CI:1.51-3.81, pa = 0.0002, respectively). Furthermore, a two-factor gene-environment interaction model of CDKN2A/B (rs10757274) and type 2 diabetes mellitus (T2DM) was identified to be the best model by GMDR (p = 0.0107), with a maximum prediction accuracy of 59.18%, and a maximum Cross-validation Consistency of 10/10. By using the ULR method, additive interaction analysis found that the combined effect resulted in T2DM-positive subjects with genotype GG/GA having an MI risk 4.38 times that of T2DM-negative subjects with genotype AA (ORadd = 4.38, 95%CI:2.56-7.47, padd < 0.0001). These results show that gene polymorphism of CDKN2A/B (rs10757274) is associated with MI risk in a Chinese population. Furthermore, T2DM is likely to have an interaction with CDKN2A/B (rs10757274) that contributes to the risk of MI.
... AMI is an inflammatory disease with multifactorial interactions, such as immunization, environmental influences, and genetic factors. The incidence of AMI shows obvious familial aggregation of a large number of genetic susceptibility genes, which play an important role in the development of diseases [6][7][8]. ...
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... 9 The finding was replicated in 2 independent reports. 10,11 In 2012, another GWAS identified 4 new loci for CAD in or near TTC32-WDR35, GUCY1A3, C6orf10-BTNL2, and ATP2B1. 12 However, these identified variants may explain little heredity of CAD in the Chinese population. ...
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... The first GWAS for CAD in a non-Caucasian population was carried out in GeneID, and identified a functional SNP rs6903956 in intron 1 of a putative gene C6orf105 (later referred to as ADTRP) as a highly significant risk variant for CAD and MI in the Chinese population [8]. The finding was later independently confirmed by two other groups [19,20]. At the same time in 2011, a large meta-analysis of four GWAS of CAD with 15,420 CAD patients and 15,062 controls was reported [12]. ...
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Several large-scale meta-GWAS identified significant association between SNP rs17465637 in the MIA3 gene and coronary artery disease (CAD) in the European ancestry populations. However, three follow-up replication studies in the Chinese populations yielded inconsistent results. In order to unequivocally determine whether SNP rs17465637 is associated with CAD, we performed an independent case control association study in the Chinese Han population and a follow-up large scale meta-analysis for SNP rs17465637. Our study included 2503 CAD patients and 2920 non-CAD controls of the Chinese Han origin. A significant association was found between SNP rs17465637 and CAD (P = 0.01, OR = 1.11). Meta-analysis included 7263 CAD patients and 8347 controls combined from five Asian populations. The association between SNP rs17465637 and CAD became highly significant (P = 4.97 × 10(-5), OR = 1.11). Similar analysis also identified significant association between SNP rs17465637 and MI (2424 cases vs. 6,536controls; P = 5.00 × 10(-3), OR = 1.10). We conclude that SNP rs17465637 in MIA3 is indeed a genetic risk factor for CAD across different ethnic populations.
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Background and aims Single nucleotide polymorphism rs6903956 has been identified as one of the genetic risk factors for coronary artery disease (CAD). However, rs6903956 lies in a non-coding locus on chromosome 6p24.1. We aim to interrogate the molecular basis of 6p24.1 containing rs6903956 risk alleles in endothelial disease biology. Methods and results We generated induced pluripotent stem cells (iPSCs) from CAD patients (AA risk genotype at rs6903956) and normal controls (GG non-risk genotype at rs6903956). CRIPSR-Cas9-based deletions (Δ63-89bp) on 6p24.1, including both rs6903956 and a short tandem repeat variant rs140361069 in linkage disequilibrium, were performed to generate isogenic iPSC-derived endothelial cells. Edited CAD endothelial cells, with removal of ‘A’ risk alleles, exhibited a global transcriptional downregulation of pathways relating to abnormal vascular physiology and activated endothelial processes. A CXC chemokine ligand on chromosome 10q11.21, CXCL12, was uncovered as a potential effector gene in CAD endothelial cells. Underlying this effect was the preferential inter-chromosomal interaction of 6p24.1 risk locus to a weak promoter of CXCL12, confirmed by chromatin conformation capture assays on our iPSC-derived endothelial cells. Functionally, risk genotypes AA/AG at rs6903956 were associated significantly with elevated levels of circulating damaged endothelial cells in CAD patients. Circulating endothelial cells isolated from patients with risk genotypes AA/AG were also found to have 10 folds higher CXCL12 transcript copies/cell than those with non-risk genotype GG. Conclusions Our study reveals the trans-acting impact of 6p24.1 with another CAD locus on 10q11.21 and is associated with intensified endothelial injury.
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Background Epistasis describes how gene‐gene interactions affect phenotypes, and could have a profound impact on human diseases such as coronary artery disease ( CAD ). The goal of this study was to identify gene‐gene interactions in CAD using an easily generalizable multi‐stage approach. Methods and Results Our forward genetic approach consists of multiple steps that combine statistical and functional approaches, and analyze information from global gene expression profiling, functional interactions, and genetic interactions to robustly identify gene‐gene interactions. Global gene expression profiling shows that knockdown of ANRIL (DQ485454) at 9p21.3 GWAS (genome‐wide association studies) CAD locus upregulates TMEM 100 and TMEM 106B . Functional studies indicate that the increased monocyte adhesion to endothelial cells and transendothelial migration of monocytes, 2 critical processes in the initiation of CAD , by ANRIL knockdown are reversed by knockdown of TMEM 106B , but not of TMEM 100 . Furthermore, the decreased monocyte adhesion to endothelial cells and transendothelial migration of monocytes induced by ANRIL overexpression was reversed by overexpressing TMEM 106B . TMEM 106B expression was upregulated by >2‐fold in CAD coronary arteries. A significant association was found between variants in TMEM 106B (but not in TMEM 100 ) and CAD ( P =1.9×10 ⁻⁸ ). Significant gene‐gene interaction was detected between ANRIL variant rs2383207 and TMEM 106B variant rs3807865 ( P =0.009). A similar approach also identifies significant interaction between rs6903956 in ADTRP and rs17465637 in MIA 3 ( P =0.005). Conclusions We demonstrate 2 pairs of epistatic interactions between GWAS loci for CAD and offer important insights into the genetic architecture and molecular mechanisms for the pathogenesis of CAD . Our strategy has broad applicability to the identification of epistasis in other human diseases.
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Identification of mutations in the ATP binding cassette transporter (ABCA1) gene in patients with Tangier disease, who exhibit reduced HDL cholesterol (HDL-C) and apolipoprotein A1 (apoA1) levels and premature coronary atherosclerosis, has led to the hypothesis that common polymorphisms in the ABCA1 gene could determine HDL-C and apoA1 levels and the risk of coronary atherosclerosis in the general population. We sequenced a 660-bp 5' fragment of the ABCA1 gene in 24 subjects and identified 3 novel polymorphisms: -477C/T, -419A/C, and -320G/C. We developed assays, genotyped 372 participants in the prospective Lipoprotein Coronary Atherosclerosis Study (LCAS), and determined the association of the variants with fasting plasma lipids and indices of quantitative coronary angiograms obtained at baseline and 2.5 years after randomization to fluvastatin or placebo. Distribution of -477C/T and -320G/C genotypes were 127 CC, 171 CT, and 74 TT and 130 GG, 168 GC, and 75 CC, respectively, and were in complete linkage disequilibrium (P<0.0001). Data for -477C/T are presented. The -419A/C variant was uncommon (present in 1 of 63 subjects). Heterozygous subjects had a modest reduction in HDL-C (P=0.09) and apoA1 (P=0.05) levels and a lesser response of apoA1 to treatment with fluvastatin (P=0.04). The mean number of coronary lesions causing 30% to 75% diameter stenosis was greater in subjects with the TT genotype (3.1+/-2.1) or CT genotype (2.9+/-1.9) than in subjects with the CC genotype (2.2+/-1.8) (P=0.002). Similarly, compared with subjects with the CC genotype, greater numbers of subjects with the TT or CT genotype had >/=1 coronary lesion (P=0.001). No association between the genotypes and progression of coronary atherosclerosis or clinical events was detected. We conclude that ABCA1 genotypes are potential risk factors for coronary atherosclerosis in the general population.
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Atherosclerotic involvement in the coronary arteries, which can result in heart attack and sudden death, is a common disease and prototypic of a complex human trait. To understand its genomic basis, eight linkage studies of sibling pairs have been performed. Although there was limited inter-study concordance of important loci, two gene variants in the leukotriene pathway (ALOX5AP and LTA4) have emerged as susceptibility factors for myocardial infarction (MI). Genome-wide association studies have also been undertaken, and the pro-inflammatory cytokine lymphotoxin-alpha (LTA), and its key ligand galectin-2 (LGALS2) have been identified as genes implicated in predisposition for heart attack. By cueing into the genomic basis for low serum LDL cholesterol levels, much work has been done to advance the importance of the serine protease PCSK9, which modulates LDL receptor function. Lifelong lowered LDL cholesterol associated with PCSK9 point mutations in 2-3% of individuals have been shown to provide marked protection from coronary artery disease (CAD). Most of the success in this field has been with the phenotype of MI, which is considerably more restrictive than CAD. Four principal and interdependent processes--lipoprotein handling, endothelial integrity, arterial inflammation, and thrombosis--have been supported as important via the clustering of genes, thus far implicated in CAD susceptibility. Of note, connecting genes in a single pathway (leukotriene), of a protein and its ligand (LTAalpha) or from one disease to another [age-related macular degeneration (AMD); complement factor H (CFH)], or even three disease characterized by inflammation (MHC2) have now been reported. Although the population attributable risk for any of the genes identified to date is limited, such discovery is likely to be accelerated in the future.
Article
Coronary artery disease remains an enormous clinical problem, affecting more than 15 million people in the United States alone, where it is the most common cause of death (accounting for one in three deaths).1 The prevalence of coronary heart disease is increasing at a particularly alarming rate in developing nations, which are ill equipped to shoulder the associated economic burden.2,3 The clinical need this represents underscores the importance of understanding the causes of coronary disease and identifying persons at risk. Much progress has been made toward these goals. We now recognize many clinical risk factors — such as hyperlipidemia . . .
Human genome variation 2006: emerging views on structural variation and large-scale SNP analysis
  • G Abecasis
  • Pk Tam
  • Cd Bustamante
  • Ea Ostrander
  • Sw Scherer
  • Sj Chanock
Abecasis G, Tam PK, Bustamante CD, Ostrander EA, Scherer SW, Chanock SJ, et al. Human genome variation 2006: emerging views on structural variation and large-scale SNP analysis. Nat Genet 2007;39:153–5.