ABSTRACT
Worldwide researchers have invested time, effort, and money during the last years to find new genes associated with diabetes susceptibility, such as LOC387761, HHEX, EXT2, and SLC30A8. The aim of the present study was to evaluate whether single-nucleotide polymorphisms (SNPs) of these genes are associated with type 2 diabetes (T2D) and metabolic traits in the Mexican population. We also assessed these SNPs in Mexican indigenous groups to identify a possible inherited susceptibility. Seven SNPs were analyzed in 789 Mexicans (234 control subjects, 455 type 2 diabetic patients, and 100 of indigenous origin), using the KASPar assay (KBioscience Company). Analysis of the data showed an association of the LOC387761 SNP rs7480010 with T2D (p = 0.019). The risk allele A of rs7480010 increased body mass index in diabetic patients (p = 0.01). In addition, there was no association between T2D and the SNPs of HHEX, EXT2, and SLC30A8. Our findings suggest that the SNP rs7480010 (LOC387761) can contribute to a failure in insulin secretion, thus increasing the susceptibility to T2D in Mexicans.
Subject(s)
Diabetes Mellitus, Type 2/genetics , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , Alleles , Body Mass Index , Cation Transport Proteins/genetics , Diabetes Mellitus, Type 2/ethnology , Genotype , Homeodomain Proteins/genetics , Humans , Insulin/genetics , Insulin/metabolism , Insulin Secretion , Mexico , N-Acetylglucosaminyltransferases/genetics , Transcription Factors/genetics , Zinc Transporter 8ABSTRACT
BACKGROUND: The major histocompatibility complex genes are located on the short arm of the human sixth chromosome; they are highly polymorphic and therefore have been very advantageous in population genetic studies. METHODS: A Mazahua group established in North Mexico State and also in nearby Michoacan state in the rainy mountain highlands (Mexico) was studied for their human leukocyte antigen (HLA)-DRB1 alleles. The relationship with other Amerindians and worldwide populations was studied by using 14,996 chromosomes from 75 different populations and calculating neighbor-joining dendrograms and correspondence multidimensional values. RESULTS: Five principal HLA allele frequencies were found in our group: DRB1*0802 (the most frequent one in this population), DRB1*0407, DRB1*0403, DRB1*0101, and DRB1*1406. Both genetic distances and correspondence analyses clearly show that our Mazahua group is genetically close to some of the most ancient groups living in Mexico (Mayos, Zapotecans, Tennek) and South American Amerindians. Amerindians remain as a group apart from the rest of the world. CONCLUSIONS: The results analyzing the HLA-DR locus suggest that Mazahua language (Otomangue) does not correlate with those of the most closely HLA-correlated ethnic groups. The present data may be useful for future transplantation programs, HLA and disease diagnosis, and pharmacogenetic studies.