[Show abstract][Hide abstract] ABSTRACT: Glycated hemoglobin (HbA1C) is used as a measure of glycemic control and also as a diagnostic criterion for diabetes mellitus. To discover novel loci harbouring common variants associated with HbA1C in East Asians, we conducted a meta-analysis of 13 genome wide association studies (N=21,026). We replicated our findings in 3 additional studies comprising 11,576 individuals of East Asian ancestry. 10 variants showed associations that reached genome wide significance in the discovery dataset of which 9 [4 novel variants at TMEM79 (P-value 1.3 × 10(-23)), HBS1L/MYB (8.5 × 10(-15)), MYO9B (9.0 × 10(-12)) and CYBA (1.1 × 10(-8)) as well as 5 variants at loci that had been previously identified (CDKAL1, G6PC2/ABCB11, GCK, ANK1, and FN3K)] showed consistent evidence of association in replication datasets. These variants explained 1.76% of the variance in HbA1C. Several of these variants (TMEM79, HBS1L/MYB, CYBA, MYO9B, ANK1, and FN3K) showed no association with either blood glucose or type 2 diabetes. Amongst individuals with non-diabetic levels of fasting glucose (<7.0 mmol/l) but elevated (>=6.5%) HbA1c, 36.1% had HbA1C<6.5% after adjustment for these 6 variants. . Our East Asian GWAS meta-analysis has identified novel variants associated with HbA1C as well as demonstrating that the effects of known variants are largely transferable across ethnic groups. Variants affecting erythrocyte parameters rather than glucose metabolism may be relevant to the use of HbA1C for diagnosing diabetes in these populations.
[Show abstract][Hide abstract] ABSTRACT: Genome-wide association studies have identified many obesity/body mass index (BMI)-associated loci in Europeans and East Asians. Since then, a large number of studies have investigated the role of BMI-associated loci in the development of type 2 diabetes (T2D). However, the results have been inconsistent. The objective of this study was to investigate the associations of eleven obesity/BMI loci with T2D risk and explore how BMI influences this risk.
We retrieved published literature from PubMed and Embase. The pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated using fixed- or random- effect models.
In the meta-analysis of forty-two studies for 11 obesity/BMI-associated loci, we observed a statistically significant association of the FTO rs9939609 polymorphism (66,425 T2D cases/239,689 normoglycaemic subjects; p=1.00×10(-41) ) and six other variants with T2D risk (17,915 T2D cases/27,531 normoglycaemic individuals: n=40,629 to 130,001; all p<0.001 for SH2B1 rs7498665, FAIM2 rs7138803, TMEM18 rs7561317, GNPDA2 rs10938397, BDNF rs925946 and NEGR1 rs2568958). After adjustment for BMI, the association remained statistically significant for four of the seven variants (all p<0.05 for FTO rs9939609, SH2B1 rs7498665, FAIM2 rs7138803, GNPDA2 rs10938397). Subgroup analysis by ethnicity demonstrated similar results.
This meta-analysis indicates that several BMI-associated variants are significantly associated with T2D risk. Some variants increase the T2D risk independent of obesity, while others mediate this risk through obesity. This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Genetic variation associated with human leukocyte antigen (HLA) genes has immunological functions and is associated with autoimmune diseases. To date, large-scale studies involving classical HLA genes have been limited by time-consuming and expensive HLA-typing technologies. To reduce these costs, single-nucleotide polymorphisms (SNPs) have been used to predict HLA-allele types. Although HLA allelic distributions differ among populations, most prediction model of HLA genes are based on Caucasian samples, with few reported studies involving non-Caucasians.
Our sample consisted of 437 Han Chinese with Affymetrix 5.0 and Illumina 550 K SNPs, of whom 214 also had data on Affymetrix 6.0 SNPs. All individuals had HLA typings at a 4-digit resolution. Using these data, we have built prediction model of HLA genes that are specific for a Han Chinese population. To optimize our prediction model of HLA genes, we analyzed a number of critical parameters, including flanking-region size, genotyping platform, and imputation. Predictive accuracies generally increased both with sample size and SNP density.
SNP data from the HapMap Project are about five times more dense than commercially available genotype chip data. Using chips to genotype our samples, however, only reduced the accuracy of our HLA predictions by only ~3%, while saving a great deal of time and expense. We demonstrated that classical HLA alleles can be predicted from SNP genotype data with a high level of accuracy (80.37% (HLA-B) ~95.79% (HLA-DQB1)) in a Han Chinese population. This finding offers new opportunities for researchers in obtaining HLA genotypes via prediction using their already existing chip datasets. Since the genetic variation structure (e.g. SNP, HLA, Linkage disequilibrium) is different between Han Chinese and Caucasians, and has strong impact in building prediction models for HLA genes, our findings emphasize the importance of building ethnic-specific models when analyzing human populations.
[Show abstract][Hide abstract] ABSTRACT: Lithium has been a first-line choice for maintenance treatment of bipolar disorders to prevent relapse of mania and depression, but many patients do not have a response to lithium treatment.
We selected subgroups from a sample of 1761 patients of Han Chinese descent with bipolar I disorder who were recruited by the Taiwan Bipolar Consortium. We assessed their response to lithium treatment using the Alda scale and performed a genomewide association study on samples from one subgroup of 294 patients with bipolar I disorder who were receiving lithium treatment. We then tested the single-nucleotide polymorphisms (SNPs) that showed the strongest association with a response to lithium for association in a replication sample of 100 patients and tested them further in a follow-up sample of 24 patients. We sequenced the exons, exon-intron boundaries, and part of the promoter of the gene encoding glutamate decarboxylase-like protein 1 (GADL1) in 94 patients who had a response to lithium and in 94 patients who did not have a response in the genomewide association sample.
Two SNPs in high linkage disequilibrium, rs17026688 and rs17026651, that are located in the introns of GADL1 showed the strongest associations in the genomewide association study (P=5.50×10(-37) and P=2.52×10(-37), respectively) and in the replication sample of 100 patients (P=9.19×10(-15) for each SNP). These two SNPs had a sensitivity of 93% for predicting a response to lithium and differentiated between patients with a good response and those with a poor response in the follow-up cohort. Resequencing of GADL1 revealed a novel variant, IVS8+48delG, which lies in intron 8 of the gene, is in complete linkage disequilibrium with rs17026688 and is predicted to affect splicing.
Genetic variations in GADL1 are associated with the response to lithium maintenance treatment for bipolar I disorder in patients of Han Chinese descent. (Funded by Academia Sinica and others.).
New England Journal of Medicine 01/2014; 370(2):119-28. · 51.66 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: ZDHHC13 is a member of DHHC-containing palmitoyl acyltransferases (PATs) family of enzymes. It functions by post-translationally adding 16-carbon palmitate to proteins through a thioester linkage. We have previously shown that mice carrying a recessive Zdhhc13 nonsense mutation causing a Zdhcc13 deficiency develop alopecia, amyloidosis and osteoporosis. Our goal was to investigate the pathogenic mechanism of osteoporosis in the context of this mutation in mice. Body size, skeletal structure and trabecular bone were similar in Zdhhc13 WT and mutant mice at birth. Growth retardation and delayed secondary ossification center formation were first observed at day 10 and at 4 weeks of age, disorganization in growth plate structure and osteoporosis became evident in mutant mice. Serial microCT from 4-20 week-olds revealed that Zdhhc13 mutant mice had reduced bone mineral density. Through co-immunoprecipitation and acyl-biotin exchange, MT1-MMP was identified as a direct substrate of ZDHHC13. In cells, reduction of MT1-MMP palmitoylation affected its subcellular distribution and was associated with decreased VEGF and osteocalcin expression in chondrocytes and osteoblasts. In Zdhhc13 mutant mice epiphysis where MT1-MMP was under palmitoylated, VEGF in hypertrophic chondrocytes and osteocalcin at the cartilage-bone interface were reduced based on immunohistochemical analyses. Our results suggest that Zdhhc13 is a novel regulator of postnatal skeletal development and bone mass acquisition. To our knowledge, these are the first data to suggest that ZDHHC13-mediated MT1-MMP palmitoylation is a key modulator of bone homeostasis. These data may provide novel insights into the role of palmitoylation in the pathogenesis of human osteoporosis.
PLoS ONE 01/2014; 9(3):e92194. · 3.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Glycogen storage disease type IIIa (GSD IIIa) is caused by a deficiency of the glycogen debranching enzyme (GDE), which is encoded by the Agl gene. GDE deficiency leads to the pathogenic accumulation of phosphorylase limit dextrin (PLD), an abnormal glycogen, in the liver, heart, and skeletal muscle. To further investigate the pathological mechanisms behind this disease and develop novel therapies to treat this disease, we generated a GDE-deficient mouse model by removing exons after exon 5 in the Agl gene. GDE reduction was confirmed by western blot and enzymatic activity assay. Histology revealed massive glycogen accumulation in the liver, muscle, and heart of the homozygous affected mice. Interestingly, we did not find any differences in the general appearance, growth rate, and life span between the wild-type, heterozygous, and homozygous affected mice with ad libitum feeding, except reduced motor activity after 50 weeks of age, and muscle weakness in both forelimb and hind legs of homozygous affected mice by using the grip strength test at 62 weeks of age. However, repeated fasting resulted in decreased survival of the knockout mice. Hepatomegaly and progressive liver fibrosis were also found in the homozygous affected mice. Blood chemistry revealed that alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) activities were significantly higher in the homozygous affected mice than in both wild-type and heterozygous mice and the activity of these enzymes further increased with fasting. Creatine phosphokinase (CPK) activity was normal in young and adult homozygous affected mice. However, the activity was significantly elevated after fasting. Hypoglycemia appeared only at a young age (3 weeks) and hyperlipidemia was not observed in our model. In conclusion, with the exception of normal lipidemia, these mice recapitulate human GSD IIIa; moreover, we found that repeated fasting was detrimental to these mice. This mouse model will be useful for future investigation regarding the pathophysiology and treatment strategy of human GSD III.
Molecular Genetics and Metabolism 01/2014; · 2.83 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To understand the genetic makeup and impact on pharmacokinetics (PK) in the Taiwanese population, we analyzed the pharmacogenetic (PG) profile and demonstrated its effects on enzyme metabolism using indapamide as an example. A multiplex mass spectrometry method was used to examine the single nucleotide polymorphism (SNP) profile of eight major phases I and II metabolic enzymes in 1,038 Taiwanese subjects. A PG/PK study was conducted in 24 healthy subjects to investigate the possible effects of 28 SNPs on drug biotransformation. Among the genetic profile analyzed, eight SNPs from CYP2A6, CYP2C19, CYP2D6, CYP2E1, CYP3A5, and UGT2B7 showed higher variant frequencies than those previously reported in Caucasians or Africans. For instance, we observed 14.7% frequency of the SNP rs5031016 (I471T) from CYP2A6 in Taiwanese, whereas 0% variation was reported in Caucasians and Africans. The PG/PK study of indapamide demonstrated that the polymorphic SNPs CYP2C9 rs4918758 and CYP2C19 rs4244285 appeared to confer lowered enzyme activity, as indicated by increased C max (25% ∼ 64%), increased area under the plasma level-time curves (30∼76%), increased area under the time infinity (43% ∼ 80%), and lower apparent clearance values than PK for wild-type indapamide. Our results reinforce the biochemical support of CYP2C19 in indapamide metabolism and identify a possible new participating enzyme CYP2C9. The PG/PK approach contributed toward understanding the genetic makeup of different ethnic groups and associations of enzymes in drug metabolism. It could be used to identify two genetic markers that enable to differentiate subjects with varied PK outcomes of indapamide.
[Show abstract][Hide abstract] ABSTRACT: The sorting nexin (SNX) family is involved in endocytosis and protein trafficking and plays multiple roles in various diseases. The role of SNX proteins in Kawasaki disease (KD) is not known. We attempted to test whether genetic SNX variation associates with the risk of coronary artery aneurysm (CAA) formation in KD.Methods and results: Chi-square tests were used to identify SNX24 genetic variants associated with KD susceptibility and CAA formation in KD; models were adjusted for fever duration and time of first administration of intravenous immunoglobulin. We obtained clinical characteristics and genotypes from KD patients (76 with CAA and 186 without CAA) in a population-based retrospective KD cohort study (n = 262). Clinical and genetic factors were associated with CAA formation in KD. In addition, endothelial cell inflammation was evaluated. Significant correlation was observed between KD with CAA complications and the rs28891 single-nucleotide polymorphism in SNX24. Patients with CC + CT genotypes had lesser CAA complications. In lipopolysaccharide-treated human umbilical vein endothelial cells, siRNA knockdown of SNX24 significantly decreased gene expression of the proinflammatory cytokines IL-1 beta, IL-6, and IL-8.
Polymorphisms in SNX24 may be used as genetic markers for the diagnosis and prognosis of CAA formation in KD.
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate, for the first time, the differences in gene expression profiles of normal and osteoarthritic (OA) subchondral bone in human subjects.
Following histological assessment of the integrity of overlying cartilage and the severity of bone abnormality by micro-computed tomography, we isolated total RNA from regions of interest from human OA (n = 20) and non-OA (n = 5) knee lateral tibial (LT) and medial tibial (MT) plateaus. A whole-genome profiling study was performed on an Agilent microarray platform and analyzed using Agilent GeneSpring GX11.5. Confirmatory quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analysis was performed on samples from 9 OA individuals to confirm differential expression of 85 genes identified by microarray. Ingenuity Pathway Analysis (IPA) was used to investigate canonical pathways and immunohistochemical staining was performed to validate protein expression levels in samples.
A total of 972 differentially expressed genes were identified (fold change >= +/- 2, P <=0.05) between LT (minimal degeneration) and MT (significant degeneration) regions from OA samples; these data implicated 279 canonical pathways in IPA. The qRT-PCR data strongly confirmed the accuracy of microarray results (R2 = 0.58, P <0.0001). Novel pathways were identified in this study including Periostin (POSTN) and Leptin (LEP), which are implicated in bone remodeling by osteoblasts.
To the best of our knowledge, this study represents the most comprehensive direct assessment to date of gene expression profiling in OA subchondral bone. This study provides insights that could contribute to the development of new biomarkers and therapeutic strategies for OA.
Arthritis research & therapy 11/2013; 15(6):R190. · 4.27 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Aim: Acute urticaria/angioedema (AUA) induced by cross-intolerance to NSAIDs is the most frequent clinical entity in hypersensitivity reactions to drugs. In this work, we conducted a genome-wide association study in Spanish and Han Chinese patients suffering from NSAID-induced AUA. Materials & methods: A whole-genome scan was performed on a total of 232 cases (112 Spanish and 120 Han Chinese) with NSAID-induced AUA and 225 unrelated controls (124 Spanish and 101 Han Chinese). Results: Although no polymorphism reached genome-wide significance, we obtained suggestive associations for three clusters in the Spanish group (RIMS1, BICC1 and RAD51L 1) and one region in the Han Chinese population (ABI3BP). Five regions showed suggestive associations after meta-analysis: HLF, RAD51L1, COL24A1, GalNAc-T13 and FBXL7. A majority of these genes are related to Ca(2+), cAMP and/or P53 signaling pathways. Conclusion: The associations described were different from those related to the metabolism of arachidonic acid and could provide new mechanisms underlying NSAID-induced AUA. Original submitted 7 June 2013; Revision submitted 19 August 2013.
[Show abstract][Hide abstract] ABSTRACT: Xq28 duplications encompassing the methyl CpG binding protein 2 (MECP2) in males exhibit a distinct phenotype, including developmental delay, facial dysmorphism, muscular hypotonia, intellectual disability, poor or absent speech, recurrent infections and early death. The vast majority of affected males inherit the MECP2 duplication from their usually asymptomatic carrier mothers. Only a few cases with Xq28 duplication originating from de novo unbalanced X/Y translocation have been reported and the paternal origin of the aberration has only been validated in three males in related to the literature. Here we present a karyotypically normal male with features characteristic of the MECP2 duplication syndrome. The genome-wide SNP genotyping shows a de novo 2.26-Mb duplication from Xq28 to the terminus. The genotypes of the SNPs within the duplicated region indicated a paternal origin. Furthermore, the results of fluorescence in situ hybridization (FISH) indicated a novel Xq:Yp translocation, characterized as der(Y)t(Y;X)(p11.32;q28), which suggests an aberrant occurred during spermatogenesis. The phenotype is compared to the previously reported cases with Xq28 duplication originated from an unbalanced X/Y translocation, and there was no specific part of the phenotype that could be contributed to the origin of parental imbalances. This report further highlights the capacity of high-molecular cytogenetic methods, such as SNP array and FISH, in the identification of submicroscopic rearrangement, structural configuration and parental origin of aberrant while in the evaluation of children with idiopathic developmental delay and intellectual disability.
[Show abstract][Hide abstract] ABSTRACT: We conducted a genome-wide association study meta-analysis of mean arterial pressure and pulse pressure among 26 600 East Asian participants (stage 1) followed by replication study of up to 28 783 participants (stage 2). For novel loci, statistical significance was determined by a P<5.0×10(-8) in joint analysis of stage 1 and stage 2 data. For loci reported by the previous mean arterial and pulse pressure genome-wide association study meta-analysis in Europeans, evidence of transethnic replication was determined by consistency in effect direction and a Bonferroni-corrected P<1.4×10(-3). No novel loci were identified by the current study. Five independent mean arterial pressure variants demonstrated robust evidence for transethnic replication including rs17249754 at ATP2B1 (P=7.5×10(-15)), rs2681492 at ATP2B1 (P=3.4×10(-7)), rs11191593 at NT5C2 (1.1×10(-6)), rs3824755 at CYP17A1 (P=1.2×10(-6)), and rs13149993 at FGF5 (P=2.4×10(-4)). Two additional variants showed suggestive evidence of transethnic replication (consistency in effect direction and P<0.05), including rs319690 at MAP4 (P=0.014) and rs1173771 at NPR3 (P=0.018). For pulse pressure, robust evidence of replication was identified for 2 independent variants, including rs17249754 at ATP2B1 (P=1.2×10(-5)) and rs11191593 at NT5C2 (P=1.1×10(-3)), with suggestive evidence of replication among an additional 2 variants including rs3824755 at CYP17A1 (P=6.1×10(-3)) and rs2681492 at ATP2B1 (P=9.0×10(-3)). Replicated variants demonstrated consistency in effect sizes between East Asian and European samples, with effect size differences ranging from 0.03 to 0.24 mm Hg for mean arterial pressure and from 0.03 to 0.21 mm Hg for pulse pressure. In conclusion, we present the first evidence of transethnic replication of several mean arterial and pulse pressure loci in an East Asian population.
[Show abstract][Hide abstract] ABSTRACT: The BLK and CD40 loci have been associated with Kawasaki disease (KD) in two genome-wide association studies (GWAS) conducted in a Taiwanese population of Han Chinese ancestry (Taiwanese) and in Japanese cohorts. Here we build on these findings with replication studies of the BLK and CD40 loci in populations of Korean and European descent. The BLK region was significantly associated with KD susceptibility in both populations. Within the BLK gene the rs2736340-located linkage disequilibrium (LD ) comprising the promoter and first intron was strongly associated with KD, with the combined results of Asian studies including Taiwanese, Japanese, and Korean populations (2,539 KD patients and 7,021 controls) providing very compelling evidence of association (rs2736340, OR = 1.498, 1.354-1.657; P = 4.74×10(-31)). We determined the percentage of B cells present in the peripheral blood mononuclear cell (PBMC) population and the expression of BLK in the peripheral blood leukocytes (leukocytes) of KD patients during the acute and convalescent stages. The percentage of B cells in the PBMC population and the expression of BLK in leukocytes were induced in patients in the acute stage of KD. In B cell lines derived from KD patients, and in purified B cells from KD patients obtained during the acute stage, those with the risk allele of rs2736340 expressed significantly lower levels of BLK. These results suggest that peripheral B cells play a pathogenic role during the acute stage of KD. Decreased BLK expression in peripheral blood B cells may alter B cell function and predispose individuals to KD. These associative data suggest a role for B cells during acute KD. Understanding the functional implications may facilitate the development of B cell-mediated therapy for KD.
PLoS ONE 08/2013; 8(8):72037-. · 3.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Runs of homozygosity (ROH) may play a role in complex diseases. In the current study, we aimed to test if ROHs are linked to the risk of autism and related language impairment. We analyzed 546,080 SNPs in 315 Han Chinese affected with autism and 1,115 controls. ROH was defined as an extended homozygous haplotype spanning at least 500 kb. Relative extended haplotype homozygosity (REHH) for the trait-associated ROH region was calculated to search for the signature of selection sweeps. Totally, we identified 676 ROH regions. An ROH region on 11q22.3 was significantly associated with speech delay (corrected p = 1.73×10(-8)). This region contains the NPAT and ATM genes associated with ataxia telangiectasia characterized by language impairment; the CUL5 (culin 5) gene in the same region may modulate the neuronal migration process related to language functions. These three genes are highly expressed in the cerebellum. No evidence for recent positive selection was detected on the core haplotypes in this region. The same ROH region was also nominally significantly associated with speech delay in another independent sample (p = 0.037; combinatorial analysis Stouffer's z trend = 0.0005). Taken together, our findings suggest that extended recessive loci on 11q22.3 may play a role in language impairment in autism. More research is warranted to investigate if these genes influence speech pathology by perturbing cerebellar functions.
PLoS ONE 01/2013; 8(8):e72056. · 3.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Kawasaki disease (KD) is pediatric systemic vasculitis with the classic complication of coronary artery aneurysm (CAA). It is the leading cause of acquired cardiovascular diseases in children. Some severe cases present with multi-organ involvement or neurological dysfunction. To identify the role of the glutamate receptor, ionotropic, N-methyl-d-aspartate 3A (GRIN3A) in KD, we investigated genetic variations in GRIN3A in a Taiwanese cohort of 262 KD patients (76 with and 186 without CAA complications). We used univariate and multivariate regression analyses to identify the associations between clinical characteristics and GRIN3A genetic variations in KD. According to univariate regression analysis, CAA formation in KD was significantly associated with fever duration (p < 0.0001), first Intravenous immunoglobulin (IVIG) used (days after day one of fever) (p < 0.0001), and the GRIN3A (rs7849782) genetic variant (p < 0.001). KD patients with GG+GC genotype showed a lower rate of developing CAA (GG+GC genotype: odds ratio = 0.26; 95% CI = 0.14-0.46). Significant associations were identified between KD with CAA complication and the GRIN3A (rs7849782) genetic variant by using multivariate regression analysis. Specifically, significant correlations were observed between KD with CAA complications and the presence of GG+GC genotypes for the GRIN3A rs7849782 single-nucleotide polymorphism (full model: odds ratio = 0.25; 95% CI = 0.14-0.46). Our results suggest that a polymorphism of the GRIN3A gene may play a role in KD pathogenesis.
PLoS ONE 01/2013; 8(11):e81384. · 3.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: OBJECTIVE: To evaluate the interaction of articular cartilage (AC) and subchondral bone (SB) through analysis of osteoarthritis (OA)-related genes of site-matched tissue. DESIGN: We developed a novel method for isolating site-matched overlying AC and underlying SB from three and four regions of interest respectively from the human knee tibial plateau (n=50). For each site, the severity of cartilage changes of OA were assessed histologically, and the severity of bone abnormalities were assessed by microcomputed tomography. An RNA isolation procedure was optimized that yielded high quality RNA from site-matched AC and SB tibial regions. Q-PCR analysis was performed to evaluate gene expression of 61 OA-associated genes for correlation with cartilage integrity and bone structure parameters. RESULTS: A total of 27 (44%) genes were coordinately up or down regulated in both tissues. The expression levels of 19 genes were statistically significantly correlated with the severity of AC degeneration and changes of SB structure; these included: ADAMTS1, ASPN, BMP6, BMPER, CCL2, CCL8, COL5A1, COL6A3, COL7A1, COL16A1, FRZB, GDF10, MMP3, OGN, OMD, POSTN, PTGES, TNFSF11 and WNT1. CONCLUSIONS: These results provide a strategy for identifying targets whose modification may have the potential to ameliorate pathological alterations and progression of disease in both AC and SB simultaneously. In addition, this is the first study, to our knowledge, to overcome the major difficulties related to isolation of high quality RNA from site-matched joint tissues. We expect this method to facilitate advances in our understanding of the coordinated molecular responses of the whole joint organ.
Osteoarthritis and Cartilage 12/2012; · 4.26 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Purpose: To identify genetic variants that predispose to type 2 diabetes (T2D) with cataract. Patients and methods: Genome-wide association study (GWAS) of T2D patients with cataract, as graded by Lens Opacities Classification System (LOCS). A total of 109 T2D patients with cataract score equal to or above 10 designated as the study group, 649 T2D patients with cataract score equal to or below 3 as the control group. Single nucleotide polymorphisms (SNPs) with p-values < 10(-5) were considered to be putatively associated with the diabetic cataract. Results: Fifteen SNPs were found to be putatively associated with diabetic cataract. These variants were located near the following genes: PPARD, CCDC102A, GBA3, NEDD9, GABRR1/2, RPS6KA2, tcag7.1163, TAC1, GALNTL1 and KIAA1671. We defined haplotype 1 to haplotype 4 from the alternative alleles of related polymorphisms. Distribution of haplotype 2 on chromosome 4 and haplotype 4 on chromosome 7 revealed significant differences (OR = 1.86 and 1.69, respectively; 95% confidence interval were 1.26-2.76 and 1.23-2.31, respectively). Conclusions: The 15 loci coded on chromosomes 4, 6, 7, 14, 16 and 22 were associated with diabetic cataract. Gene functions are either with mechanisms of regulating blood sugar or formation of cataract. High linkage disequilibrium appeared on chromosome 4p15.31 and chromosome 7q21.3.
[Show abstract][Hide abstract] ABSTRACT: Purpose: Diabetic retinopathy (DR) is one of the most common complications of diabetes mellitus (DM). The susceptibility genes responsible for increasing the risk for DR in type 2 diabetes (T2D) were sought in this study. Methods: A case-control study was carried out, comprising 749 unrelated T2D individuals with (n = 174) and without (n = 575) DR. Genotypic distributions of single nucleotide polymorphisms (SNPs) were determined for subjects with and without DR. Results: Eight chromosome 6 SNPs, having the most significant differences, were delineated: rs10499298, rs10499299, rs17827966, rs1224329, rs1150790, rs713050, rs2518344 and rs487083; all were associated with genes TMEM217, MRPL14 and GRIK2. After adjusting for the duration of DM and levels of hemoglobin A(1c), the TT genotype of rs713050, and the AG + AA genotypes of rs2518344 and rs10499298, differed significantly between those with and without DR. Haplotype analysis revealed haplotype C-A-C, residing in rs10499299, rs10499298 and rs17827966, to have significant linkage disequilibrium. Conclusions: We identified new loci on chromosome 6 associated to DR; all loci showed high levels of linkage disequilibrium.
[Show abstract][Hide abstract] ABSTRACT: Chronic kidney disease (CKD), impairment of kidney function, is a serious public health problem, and the assessment of genetic factors influencing kidney function has substantial clinical relevance. Here, we report a meta-analysis of genome-wide association studies for kidney function-related traits, including 71,149 east Asian individuals from 18 studies in 11 population-, hospital- or family-based cohorts, conducted as part of the Asian Genetic Epidemiology Network (AGEN). Our meta-analysis identified 17 loci newly associated with kidney function-related traits, including the concentrations of blood urea nitrogen, uric acid and serum creatinine and estimated glomerular filtration rate based on serum creatinine levels (eGFRcrea) (P < 5.0 × 10(-8)). We further examined these loci with in silico replication in individuals of European ancestry from the KidneyGen, CKDGen and GUGC consortia, including a combined total of ∼110,347 individuals. We identify pleiotropic associations among these loci with kidney function-related traits and risk of CKD. These findings provide new insights into the genetics of kidney function.
[Show abstract][Hide abstract] ABSTRACT: Recent meta-analyses of European ancestry subjects show strong evidence for association between smoking quantity and multiple genetic variants on chromosome 15q25. This meta-analysis extends the examination of association between distinct genes in the CHRNA5-CHRNA3-CHRNB4 region and smoking quantity to Asian and African American populations to confirm and refine specific reported associations. Association results for a dichotomized cigarettes smoked per day phenotype in 27 datasets (European ancestry (N = 14,786), Asian (N = 6,889), and African American (N = 10,912) for a total of 32,587 smokers) were meta-analyzed by population and results were compared across all three populations. We demonstrate association between smoking quantity and markers in the chromosome 15q25 region across all three populations, and narrow the region of association. Of the variants tested, only rs16969968 is associated with smoking (P < 0.01) in each of these three populations (odds ratio [OR] = 1.33, 95% CI = 1.25-1.42, P = 1.1 × 10(-17) in meta-analysis across all population samples). Additional variants displayed a consistent signal in both European ancestry and Asian datasets, but not in African Americans. The observed consistent association of rs16969968 with heavy smoking across multiple populations, combined with its known biological significance, suggests rs16969968 is most likely a functional variant that alters risk for heavy smoking. We interpret additional association results that differ across populations as providing evidence for additional functional variants, but we are unable to further localize the source of this association. Using the cross-population study paradigm provides valuable insights to narrow regions of interest and inform future biological experiments.