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ABSTRACT: The aim of this study was to investigate the possible role of the CCR5 59029 A→G promoter point mutation polymorphism in determining the susceptibility to rheumatoid factor-positive and rheumatoid factor-negative rheumatoid arthritis. This polymorphism was assessed in 85 seropositive and 39 seronegative rheumatoid arthritis patients and in 126 healthy individuals of the same geographic and ethnic origin. We found an increase in the genetic frequency of the A allele in the 59029 A→G promoter region of the CCR5 receptor in patients with rheumatoid arthritis compared with healthy controls (p = 0.01; OR = 1.5, 95% CI (1.0-2.2). Likewise, the homozygous state for the A allele was found to be more frequent in rheumatoid arthritis patients, again when compared with healthy controls (p = 0.03; OR = 1.8, 95% CI 1.0-3.0). The increased frequency of the A allele was more evident in the more benign, seronegative rheumatoid arthritis group when compared with controls (p = 0.003; OR 2.4 95% CI 1.3-4.4), and when combining the A homozygous and the AG heterozygous patients compared with healthy subjects. These results suggest that this CCR5 promoter polymorphism seems to play an important role in determining different clinical courses in both forms of rheumatoid arthritis.
European cytokine network. 06/2012; 23(2):25-8.
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ABSTRACT: Aplastic anemia (AA) is a hematological disorder characterized by pancytopenia in peripheral blood and hypoplasia in the bone marrow; the majority of cases have no known etiology, but it is thought that genetic and environmental factors can be involved in its pathogenesis. From the genetic viewpoint, it has been reported a significant increase frequency of the human leukocyte antigen HLA-DRB1(∗)15 in patients with AA as compared to ethnically matched healthy controls, this is true in different populations worldwide, which would suggests that this allele participates in the immune regulation of the disease.
To determine gene frequencies of HLA-DRB1 alleles in Mexican mestizo patients with AA.
We analyzed and compared the HLA-DRB1 alleles in 36 Mexican mestizo patients (female gender, n=13; male gender, n=23) with AA to those present in 201 umbilical cord blood (UCB) samples as a control group, this was done by means of the polymerase chain reaction-single specific primer (PCR-SSP) technique.
Analysis of gene frequencies of HLA-DRB1(∗) alleles exhibits a significant increase of HLA-DRB1(∗)15 allele in the group of patients with AA as compared to those present in the control group (15.27% vs. 2.23%, respectively; p=1×10(-5); odds ratio [OR]=9.3; 95% confidence interval [95% CI]=3.2-27.8).
Our results showed a positive association of the DRB1(∗)15 allele in Mexican patients with aplastic anemia, which coincides with that reported internationally. In addition, we think that this allele was introduced to the Mexican population structure inherited from European ancestry.
Human immunology 05/2012; 73(8):840-3. · 2.55 Impact Factor
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Janette Furuzawa-Carballeda,
Guadalupe Lima,
Perla Simancas,
Dolores Ramos-Bello,
Margaret Simancas,
Ian C Bostock,
Mario Vilatobá,
Bernardo Gabilondo, Julio Granados,
Luis Morales-Buenrostro,
Josefina Alberú,
Luis Llorente
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ABSTRACT: Regulatory Foxp3-expressing T cells (Tregs), IL-10-producing B cells (Bregs), and IDO-expressing dendritic cells (DCregs) downregulate inflammatory processes and induces peripheral tolerance. These subpopulations also might participate in maintaining allograft immunological quiescence in kidney transplant recipients (KTRs) with an excellent long-term graft function under immunosuppression (ELTGF). The aim of the study was to characterize and to enumerate peripheral Tregs, Bregs, and DCregs in KTR with an ELTGF for more than 5 years after transplant. Fourteen KTR with an ELTGF, 9 KTR with chronic graft dysfunction (CGD), and 12 healthy donors (HDs) were included in the study. CD19(+)-expressing peripheral B lymphocytes were purified by positive selection. IL-10-producing B cells, CD4(+)/CD25(hi), and CD8(+)/CD28(-) Tregs, as well as CCR6(+)/CD123(+)/IDO(+) DCs, were quantitated by flow cytometry. IL-10-producing Bregs (immature/transitional, but not CD19(+)/CD38(hi)/CD24(hi)/CD27(+)B10 cells), CCR6(+)/CD123(+)/IDO(+) DCs, and Tregs from ELTGF patients had similar or higher percentages versus HD (P < 0.05). By contrast, number of Tregs, DCregs, and Bregs except for CD27(+)B10 cells from CGD patients had lower levels versus HD and ELTGF patients (P < 0.05). The findings of this exploratory study might suggest that in ELTGF patients, peripheral tolerance mechanisms could be directly involved in the maintenance of a quiescent immunologic state and graft function stability.
Journal of Transplantation 01/2012; 2012:256960.
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ABSTRACT: Mycobacterium tuberculosis (Mtb) infection is a major international public health problem. One-third of the world's population is thought to have latent tuberculosis, a condition where individuals are infected by the intracellular bacteria without active disease but are at risk for reactivation, if their immune system fails. Here, we discuss the role of nonspecific inflammatory responses mediated by cytokines and chemokines induced by interaction of innate receptors expressed in macrophages and dendritic cells (DCs). We also review current information regarding the importance of several cytokines including IL-17/IL-23 in the development of protective cellular and antibody-mediated protective responses against Mtb and their influence in containment of the infection. Finally, in this paper, emphasis is placed on the mechanisms of failure of Mtb control, including the immune dysregulation induced by the treatment with biological drugs in different autoimmune diseases. Further functional studies, focused on the mechanisms involved in the early host-Mtb interactions and the interplay between host innate and acquired immunity against Mtb, may be helpful to improve the understanding of protective responses in the lung and in the development of novel therapeutic and prophylactic tools in TB.
Clinical and Developmental Immunology 01/2012; 2012:193923. · 1.84 Impact Factor
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ABSTRACT: The study of genetic information can reveal a reconstruction of human population's history. We sequenced the entire mtDNA control region (positions 16.024 to 576 following Cambridge Reference Sequence, CRS) of 605 individuals from seven Mesoamerican indigenous groups and one Aridoamerican from the Greater Southwest previously defined, all of them in present Mexico. Samples were collected directly from the indigenous populations, the application of an individual survey made it possible to remove related or with other origins samples. Diversity indices and demographic estimates were calculated. Also AMOVAs were calculated according to different criteria. An MDS plot, based on FST distances, was also built. We carried out the construction of individual networks for the four Amerindian haplogroups detected. Finally, barrier software was applied to detect genetic boundaries among populations. The results suggest: a common origin of the indigenous groups; a small degree of European admixture; and inter-ethnic gene flow. The process of Mesoamerica's human settlement took place quickly influenced by the region's orography, which development of genetic and cultural differences facilitated. We find the existence of genetic structure is related to the region's geography, rather than to cultural parameters, such as language. The human population gradually became fragmented, though they remained relatively isolated, and differentiated due to small population sizes and different survival strategies. Genetic differences were detected between Aridoamerica and Mesoamerica, which can be subdivided into "East", "Center", "West" and "Southeast". The fragmentation process occurred mainly during the Mesoamerican Pre-Classic period, with the Otomí being one of the oldest groups. With an increased number of populations studied adding previously published data, there is no change in the conclusions, although significant genetic heterogeneity can be detected in Pima and Huichol groups. This result may be explained because populations historically assigned as belonging to the same group were, in fact, different indigenous populations.
PLoS ONE 01/2012; 7(9):e44666. · 4.09 Impact Factor
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ABSTRACT: Increased levels of tumor necrosis factor alpha (TNF-α) in patients with dengue have been reported. Various polymorphisms have been identified in the promoter region of the TNF-α gene that may affect its transcription. The purpose of the present study was to evaluate the relationship between polymorphisms of TNF-α gene and the genetic susceptibility to dengue fever in a group of patients from Morelos State, Mexico. The TNF-α polymorphisms (positions -238 and -308) were determined by PCR-RFLP technique in 130 patients with dengue (85 with dengue fever and 45 with dengue hemorrhagic fever) and 169 healthy controls. The patients were selected from cases reported in Morelos State from 1997 to 2003. The whole group of dengue patients showed a decreased frequency of TNF-α -238 A allele when compared to healthy controls (p = 0.01, OR = 0.19, 95%CI = 0.02-0.78). When the analysis was made separately in dengue fever and dengue hemorrhagic fever patients, the decreased frequency of TNF-α -238 A allele only remained significant in patients with DHF when compared to healthy controls (p = 0.034). This work suggests a possible association of TNF-α -238 A allele with protection to develop symptomatic disease.
Acta tropica 06/2011; 120(1-2):67-71. · 2.22 Impact Factor
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Margarita Camorlinga-Ponce,
Guillermo Perez-Perez,
Gerardo Gonzalez-Valencia,
Irma Mendoza,
Rosenda Peñaloza-Espinosa,
Irma Ramos,
Dangeruta Kersulyte,
Adriana Reyes-Leon,
Carolina Romo, Julio Granados,
Leopoldo Muñoz,
Douglas E Berg,
Javier Torres
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ABSTRACT: It is valuable to extend genotyping studies of Helicobacter pylori to strains from indigenous communities across the world to better define adaption, evolution, and associated diseases. We aimed to genetically characterize both human individuals and their infecting H. pylori from indigenous communities of Mexico, and to compare them with those from other human groups. We studied individuals from three indigenous groups, Tarahumaras from the North, Huichols from the West and Nahuas from the center of Mexico. Volunteers were sampled at their community site, DNA was isolated from white blood cells and mtDNA, Y-chromosome, and STR alleles were studied. H. pylori was cultured from gastric juice, and DNA extracted for genotyping of virulence and housekeeping genes. We found Amerindian mtDNA haplogroups (A, B, C, and D), Y-chromosome DYS19T, and Amerindian STRs alleles frequent in the three groups, confirming Amerindian ancestry in these Mexican groups. Concerning H.pylori cagA phylogenetic analyses, although most isolates were of the Western type, a new Amerindian cluster neither Western nor Asian, was formed by some indigenous Mexican, Colombian, Peruvian and Venezuelan isolates. Similarly, vacA phylogenetic analyses showed the existence of a novel Amerindian type in isolates from Alaska, Mexico and Colombia. With hspA strains from Mexico and other American groups clustered within the three major groups, Asian, African or European. Genotyping of housekeeping genes confirmed that Mexican strains formed a novel Asian-related Amerindian group together with strains from remote Amazon Aborigines. This study shows that Mexican indigenous people with Amerindian markers are colonized with H. pylori showing admixture of Asian, European and African strains in genes known to interact with the gastric mucosa. We present evidence of novel Amerindian cagA and vacA alleles in indigenous groups of North and South America.
PLoS ONE 01/2011; 6(11):e27212. · 4.09 Impact Factor
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ABSTRACT: Onychomycosis is multifactorial in origin. Studies have suggested an autosomal dominant pattern of inheritance and human leukocyte antigen DR4 (HLA-DR4) has been shown to protect against onychomycosis in an Ashkenazi Jewish population.
This study investigates HLA class II association in a Mexican Mestizo population with Trichophyton rubrum onychomycosis.
This was a prospective case-control study. Mexican Mestizos with a clinical diagnosis of onychomycosis and culture positive for T. rubrum were recruited, together with age- and sex-matched controls. First-degree relatives were also investigated for onychomycosis. Case-control samples were HLA typed by polymerase chain reaction sequence-specific primer based analysis.
Twenty-one cases and 42 controls were recruited with a mean age of 40 years (range: 18-58 years). HLA-DR6 was found in seven (33%) cases and 19 (45%) controls [P < 0.023, odds ratio (OR) = 0.088, 95% confidence interval (CI): 0.01-0.71]. Six (29%) cases and three (7%) controls had an affected child (P < 0.043, OR = 9.15, 95% CI: 1.07-78.31), and 13 (62%) cases and 12 (29%) controls had an affected first-degree relative (P < 0.02, OR = 4.0, 95% CI: 1.1-14.3).
These results suggest that HLA-DR6 confers protection against the development of onychomycosis in a Mexican Mestizo population. Having an affected first-degree relative significantly increases the risk of onychomycosis, suggesting genetic susceptibility.
International journal of dermatology 12/2010; 49(12):1406-9. · 1.18 Impact Factor
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ABSTRACT: The skin wart is a benign proliferation of the skin and mucous, secondary to human papillomavirus (HPV) infection.
The objective of this study is to determine gene frequencies of HLA-DR alleles in Mexican patients with skin warts and compare them with those present in ethnically matched healthy subjects.
Fifty-two patients with clinically and histologically confirmed skin warts from the Dermatology Outpatient Clinic, with results of high-resolution DNA typing for HLA-DR polymorphism.
HLA-DR3 and DR9 were increased (P = 0.0029, OR: 2.5, 95% CI: 1.3–4.7 and P = 0.0062, OR: 5.4, 95% CI: 1.4–19.5, respectively), and HLA-DR6 allele was found decreased (P = 0.0002).
The major histocompatibility complex contribution in the infection and elimination of the virus is not clear and perhaps also contributes to a series of events not well established yet.
This study follows the preponderant role of class II genes in the susceptibility or resistance to the development of skin warts caused by HPV infection.
International journal of dermatology 12/2010; 49(12):1376-9. · 1.18 Impact Factor
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ABSTRACT: We analyzed the HLA class II allele frequencies in 50 healthy unrelated Mayan individuals. The relationship with other worldwide populations was studied by using HLA data from 71 different populations. The most frequent alleles were HLA-DRB1*04, HLA-DRB1*01, HLA-DQB1*0302 and HLA-DQB1*0501. When comparisons with other Mexican Amerindian groups were made, some differences were observed. Mayans showed an increased frequency of HLA-DRB1*01 when compared to Nahuas, Mayos, Teenek and Mazatecans (p < 0.05), whereas the HLA-DRB1*04 was increased in Mayans when compared to Nahuas (p < 0.05). The analysis of HLA-DQB1 alleles showed an increased frequency of DQB1*0302 in Mayans when compared to Nahuas and Mazatecans (p < 0.05), whereas the frequency of HLA-DQB1*0301 was decreased in Mayans when compared to Nahuas, Mayos, Teenek and Mazatecans (p < 0.05). Decreased frequency of HLA-DQB1*0501 in Mayans when compared to Nahuas was found. Neighbour Joining dendrogram shows that Mexican Mayans are genetically close to some of the most ancient groups living in Mexico and some South American Amerindians. However, Guatemalan Mayans do not cluster together with Mexican Mayas showing that languages do not correlate with genes, particularly in Amerindians. The data corroborate the restricted polymorphism of HLA-DRB1 and DQB1 alleles and the high frequency of HLA-DRB1*04 and HLA-DQB1*0302 in Mayans from Mexico.
Immunological Investigations 10/2010; 40(1):101-11. · 1.47 Impact Factor
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Víctor Acuña-Alonzo,
Teresa Flores-Dorantes,
Janine K Kruit,
Teresa Villarreal-Molina,
Olimpia Arellano-Campos,
Tábita Hünemeier,
Andrés Moreno-Estrada,
Ma Guadalupe Ortiz-López,
Hugo Villamil-Ramírez,
Paola León-Mimila, [......],
Carlos A Aguilar-Salinas,
Ruben Lisker,
Regina S Moises,
Marta Menjivar,
Francisco M Salzano,
William C Knowler,
M Cátira Bortolini,
Michael R Hayden,
Leslie J Baier,
Samuel Canizales-Quinteros
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ABSTRACT: It has been suggested that the higher susceptibility of Hispanics to metabolic disease is related to their Native American heritage. A frequent cholesterol transporter ABCA1 (ATP-binding cassette transporter A1) gene variant (R230C, rs9282541) apparently exclusive to Native American individuals was associated with low high-density lipoprotein cholesterol (HDL-C) levels, obesity and type 2 diabetes in Mexican Mestizos. We performed a more extensive analysis of this variant in 4405 Native Americans and 863 individuals from other ethnic groups to investigate genetic evidence of positive selection, to assess its functional effect in vitro and to explore associations with HDL-C levels and other metabolic traits. The C230 allele was found in 29 of 36 Native American groups, but not in European, Asian or African individuals. C230 was observed on a single haplotype, and C230-bearing chromosomes showed longer relative haplotype extension compared with other haplotypes in the Americas. Additionally, single-nucleotide polymorphism data from the Human Genome Diversity Panel Native American populations were enriched in significant integrated haplotype score values in the region upstream of the ABCA1 gene. Cells expressing the C230 allele showed a 27% cholesterol efflux reduction (P< 0.001), confirming this variant has a functional effect in vitro. Moreover, the C230 allele was associated with lower HDL-C levels (P = 1.77 x 10(-11)) and with higher body mass index (P = 0.0001) in the combined analysis of Native American populations. This is the first report of a common functional variant exclusive to Native American and descent populations, which is a major determinant of HDL-C levels and may have contributed to the adaptive evolution of Native American populations.
Human Molecular Genetics 04/2010; 19(14):2877-85. · 7.64 Impact Factor
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ABSTRACT: Hypersensitivity Pneumonitis (HP) is a lung inflammatory disorder caused by inhalation of organic particles by a susceptible host. However, only a small proportion of individuals exposed to HP-associated antigens develop the disease, suggesting that additional host/environmental factors may play a role. We have previously found that genetic susceptibility associated to the major histocompatibility complex (MHC) plays an important role in this disease. The low molecular weight proteosome (LMP, currently named PSMB) genes code for subunits of the proteosome, a multimeric enzymatic complex that degrades proteins into peptides in order to be presented in the MHC class I pathway. We hypothesized that polymorphisms in PSMB8 or PSMB9 genes could be involved in the susceptibility to HP. Thus, in this study we analyzed the polymorphic site at amino acid position 60 (Arg/His) of the fourth exon in the PSMB9 gene and the amino acid position 49 (Gln/Lys) in the second exon of PSMB8 gene in 50 Mexican patients with HP and 50 healthy ethnically matched controls. PSMB typing was performed using polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP). Our results demonstrated that HP patients had a significant increase of the PSMB8 KQ genotype frequency (OR = 7.25, CI = 2.61-21.3; p = 0.000034). No differences were found in the distribution of PSMB9 alleles/genotypes. However, PSMB9-RH/PSMB8 KQ haplotype was significantly increased in HP patients (OR = 6.77, CI = 1.34-65.31, p < 0.02). These findings suggest that PSMB8 KQ genotype could increase the risk to develop hypersensitivity pneumonitis.
Respiratory medicine 02/2010; 104(6):889-94. · 2.33 Impact Factor
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ABSTRACT: We previously reported that the -2518 MCP-1 genotype GG increases the likelihood of developing tuberculosis (TB) in non-BCG-vaccinated Mexicans and Koreans. Here, we tested the hypothesis that this genotype, alone or together with the -1607 MMP-1 functional polymorphism, increases the likelihood of developing TB in BCG-vaccinated individuals. We conducted population-based case-control studies of BCG-vaccinated individuals in Mexico and Peru that included 193 TB cases and 243 healthy tuberculin-positive controls from Mexico and 701 TB cases and 796 controls from Peru. We also performed immunohistochemistry (IHC) analysis of lymph nodes from carriers of relevant two-locus genotypes and in vitro studies to determine how these variants may operate to increase the risk of developing active disease. We report that a joint effect between the -2518 MCP-1 genotype GG and the -1607 MMP-1 genotype 2G/2G consistently increases the odds of developing TB 3.59-fold in Mexicans and 3.9-fold in Peruvians. IHC analysis of lymph nodes indicated that carriers of the two-locus genotype MCP-1 GG MMP-1 2G/2G express the highest levels of both MCP-1 and MMP-1. Carriers of these susceptibility genotypes might be at increased risk of developing TB because they produce high levels of MCP-1, which enhances the induction of MMP-1 production by M. tuberculosis-sonicate antigens to higher levels than in carriers of the other two-locus MCP-1 MMP-1 genotypes studied. This notion was supported by in vitro experiments and luciferase based promoter activity assay. MMP-1 may destabilize granuloma formation and promote tissue damage and disease progression early in the infection. Our findings may foster the development of new and personalized therapeutic approaches targeting MCP-1 and/or MMP-1.
PLoS ONE 01/2010; 5(1):e8881. · 4.09 Impact Factor
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ABSTRACT: We describe the analysis of the Major Histocompatibility Complex (MHC) class II polymorphism in Mexican Mestizo population. The study provides the HLA-DRB1, DQA1 and DQB1 allele frequencies in 99 Mexican Mestizos. DNA from these individuals was typed by PCR followed by hybridization using sequence specific oligonucleotides (PCR-SSO). The relationship with other worldwide populations was studied by using HLA data from 69 different populations and calculating neighbor-joining dendrograms and correspondence multidimensional values. The highest frequencies were for DRB1*0802 (allele frequency = 0.151), DRB1*0701 (allele frequency = 0.111) and DRB1*0407 (allele frequency = 0.106). Among the eight DQA1 alleles detected, the most frequent were DQA1*03011 (allele frequency = 0.257), DQA1*0501 (allele frequency = 0.227) and DQA1*0401 (allele frequency = 0.166). Twelve DQB1 alleles were found and four of them, DQB1*0302 (allele frequency = 0.237), DQB1*0301 (allele frequency = 0.176), DQB1*0201 (allele frequency = 0.166) and DQB1*0402 (allele frequency = 0.166) showed the highest frequencies. The haplotype DRB1*0802-DQA1*0401-DQB1*0402 (0.151) predominated clearly, followed by DRB1*0701-DQA1*0201-DQB1*0201 (0.111) and DRB1*0407-DQA1*03011-DQB1*0302 (0.101). Both genetic distances and correspondence analyses showed that Mexicans clustered with Amerindian population. These results suggest that the Mexican Mestizo population be principally characterized by haplotypes presents in Amerindian and Caucasian populations with a low frequency of Black haplotypes. In summary, the HLA class II haplotype frequencies demonstrated the tri-racial component existing in Mexican Mestizos.
Immunological Investigations 01/2010; 39(3):268-83. · 1.47 Impact Factor
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ABSTRACT: The aim of this review is to present current information on transplantation research regarding the role of indoleamine 2,3 dioxygenase in immune regulation. We present the basic mechanisms by which the enzyme is expressed, followed by tryptophan catabolism that leads to midg1 phase arrest and apoptosis. Other effects proposed, although not yet completely proven and generally accepted, include T-cell development suppression, secretion of regulatory cytokines such as IL10, and generation of new T regulatory cells. Clinical studies are being performed worldwide; thus, our goal is to focus on the clinical potential relevance of the enzyme rather than a presentation on a molecular basis so that health care providers concerning transplantation are aware of this promising field in immunology and therapeutics. We do emphasize the fact that information regarding the role of indoleamine 2,3 dioxygenase in human beings is still scarce
Transplantation reviews 01/2010; 24(3):160-5.
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Liliana Encinales,
Joaquin Zuñiga,
Julio Granados-Montiel,
Maria Yunis, Julio Granados,
Ingrid Almeciga,
Olga Clavijo,
Carlos Awad,
Vilma Collazos,
María Inés Vargas-Rojas,
José Luis Bañales-Mendez,
Lilia Vazquez-Castañeda,
Joel N Stern,
Viviana Romero,
Masha Fridkis-Hareli,
Masha Frindkis-Hareli,
Daniel Terreros,
Marcelo Fernandez-Viña,
Edmond J Yunis
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ABSTRACT: The most common test to identify latent tuberculosis is the tuberculin skin test that detects T cell responses of delayed type hypersensitivity type IV. Since it produces false negative reactions in active tuberculosis or in high-risk persons exposed to tuberculosis patients as shown in this report, we studied antibody profiles to explain the anergy of such responses in high-risk individuals without active infection. Our results showed that humoral immunity against tuberculin, regardless of the result of the tuberculin skin test is important for protection from active tuberculosis and that the presence of high antibody titers is a more reliable indicator of infection latency suggesting that latency can be based on the levels of antibodies together with in vitro proliferation of peripheral blood mononuclear cells in the presence of the purified protein derivative. Importantly, anti-tuberculin IgG antibody levels mediate the anergy described herein, which could also prevent reactivation of disease in high-risk individuals with high antibody titers. Such anti-tuberculin IgG antibodies were also found associated with blocking and/or stimulation of in vitro cultures of PBMC with tuberculin. In this regard, future studies need to establish if immune responses to Mycobacterium tuberculosis can generate a broad spectrum of reactions either toward Th1 responses favoring stimulation by cytokines or by antibodies and those toward diminished responses by Th2 cytokines or blocking by antibodies; possibly involving mechanisms of antibody dependent protection from Mtb by different subclasses of IgG.
Molecular Immunology 12/2009; 47(5):1066-73. · 2.90 Impact Factor
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Benito Estrada-Mena,
F Javier Estrada,
Raúl Ulloa-Arvizu,
Miriam Guido,
Rocío Méndez,
Ramón Coral,
Thelma Canto, Julio Granados,
Rodrigo Rubí-Castellanos,
Héctor Rangel-Villalobos,
Alejandro García-Carrancá
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ABSTRACT: All major ABO blood alleles are found in most populations worldwide, whereas the majority of Native Americans are nearly exclusively in the O group. O allele molecular characterization could aid in elucidating the possible causes of group O predominance in Native American populations. In this work, we studied exon 6 and 7 sequence diversity in 180 O blood group individuals from four different Mesoamerican populations. Additionally, a comparative analysis of genetic diversity and population structure including South American populations was performed. Results revealed no significant differences among Mesoamerican and South American groups, but showed significant differences within population groups attributable to previously detected differences in genetic drift and founder effects throughout the American continent. Interestingly, in all American populations, the same set of haplotypes O(1), O(1v), and O(1v(G542A)) was present, suggesting the following: (1) that they constitute the main genetic pool of the founding population of the Americas and (2) that they derive from the same ancestral source, partially supporting the single founding population hypothesis. In addition, the consistent and restricted presence of the G542A mutation in Native Americans compared to worldwide populations allows it to be employed as an Ancestry informative marker (AIM). Present knowledge of the peopling of the Americas allows the prediction of the way in which the G542A mutation could have emerged in Beringia, probably during the differentiation process of Asian lineages that gave rise to the founding population of the continent.
American Journal of Physical Anthropology 10/2009; 142(1):85-94. · 2.82 Impact Factor
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ABSTRACT: Several studies have evaluated the effect of soy protein or soluble fiber on serum cholesterol in hypercholesterolemic subjects, with different results. We hypothesized that this response is associated with the presence of polymorphisms in genes encoding proteins involved in lipoprotein metabolism or reverse cholesterol transport. Thus, the aims of the present work were to study the effectiveness of a dietary portfolio consisting of a combination of soy protein and soluble fiber integrated in a low saturated fat (LSF) diet on blood lipids in a Mexican group with hyperlipidemia and to determine the association between responsiveness to the diet and the frequency of apolipoprotein (Apo) E and ApoA1 and ABCG5/8 polymorphisms. Forty-three hyperlipidemic subjects (20 men and 23 women) were given an LSF diet for 1 month, followed by an LSF diet that included 25 g of soy protein and 15 g of soluble fiber daily for 2 months. After the 3-month dietary intervention, serum total cholesterol (TC) significantly decreased by 20.6%, and serum triglycerides (TGs) decreased by 40.4%. Fifty-one percent of the subjects had a reduction more than 20% in serum TC, and 77% of the subjects had a reduction more than 20% in serum TG (hyperresponders). Approximately 14% of the hypercholesterolemic subjects had the ABCG8 (52 G/C) polymorphism, 65% had the ABCG5 (1950 C/G and G/G) polymorphism, 53.5% had the ApoA1 (-75 G/A and A/A) polymorphism, and 23.3% had the ApoE (3/4) polymorphism. Independently of genotype, the combination of cholesterol-lowering foods in an LSF diet significantly reduced serum TC and TG in Mexican hypercholesterolemic subjects.
Nutrition research (New York, N.Y.) 10/2009; 29(10):728-35. · 1.20 Impact Factor
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ABSTRACT: The aim of this study was to study the association between the HLA-DRB1 alleles and the clinical course of ulcerative colitis (UC).
Seventy-five Mexican patients with UC were studied. High resolution HLA typing was performed using Polymerase Chain Reaction-Sequence Specific Oligonucleotide PCR-SSO reverse dot blot and Polymerase Chain Reaction-single specific primer PCR-SSP. Molecular typing techniques were applied to define HLA-DRB1 alleles.
Seventy-five patients (36 female patients, 39 male patients) were studied. Significant associations were found between some HLA-DRB1 alleles and the clinical course of disease: initial active and then inactive and the HLA-DRB1*14 allele (P = 0.03; OR = 4.63; 95% CI: 1.08-21.23); and HLA-DRB1*08 allele (P = 0.04; OR = 4.34; 95% CI: 1.9-33.3). On the other hand, the HLA-DRB1*07 (P = 0.001; OR = 9.76 95% CI: 1.55-65.56) was significantly associated with steroid dependence in UC patients.
This study suggests that HLA-DRB1 alleles were associated with the clinical course of disease and steroid dependence in UC patients.
Colorectal Disease 09/2009; 12(12):1231-5. · 2.93 Impact Factor
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ABSTRACT: Host genetics in dengue hemorrhagic fever (DHF) pathophysiology has not been extensively investigated. Most studies have focused on HLA in different populations; however these reported associations have not been replicated. We performed a case-control study to analyze possible associations of HLA-A, HLA-B, HLA-Cw, HLA-DRB1 and HLA-DQB1 alleles with clinical disease severity caused by dengue virus infection. Our population consisted of 39 individuals (DF: 23, DHF: 16) and 34 healthy controls from the State of Morelos, Mexico. HLA loci were genotyped by nucleotide sequencing method. Statistical analyses revealed associations in three alleles: HLA-B*35 was negatively associated with symptomatic disease (p<1x10(-4), p(c)=0.01, OR=0.12, 95%CI=0.037-0.39), and DF (p=0.0007, p(c)=0.03, OR=0.13, 95%CI=0.031-0.51). HLA-DQB1*0302 was positively associated with DHF (p=0.018, p(c)=NS, OR=5.02, 95%CI=1.05-25.34), and negatively with DF (p=0.011, p(c)=NS, OR=0.23, 95%CI=0.06-0.84). HLA-DQB1*0202 was positively associated with DF only (p=0.012, p(c)=NS, OR=7.0, 95%CI=1.11-73.8). We identified possible associations of HLA-B and HLA-DQB1 alleles with the risk of developing symptomatic disease, DF and DHF in a Mexican Mestizo population.
Acta tropica 08/2009; 112(2):193-7. · 2.22 Impact Factor
