Major Histocompatibility Complex Class I and II Allele Frequencies and Disease Associations in Mexicans: A Systematic Review and Meta-Analysis.

BACKGROUND

The major histocompatibility complex (MHC) plays a crucial role in immune responses and is associated with disease susceptibility. This study systematically reviews MHC class I and class II allele frequencies and their associations with diseases in the Mexican population from 1979 to 2023.

METHODS

A systematic review following PRISMA guidelines was conducted. Reports were obtained from the Allele Frequency Net Database and PubMed using keywords related to HLA and Mexican populations. A total of 776 reports were screened, and 214 were retained for final analysis. Seventy-six studies comprising allele frequency data from over 20,000 individuals across Mexican states and indigenous communities were analyzed. In addition, over 138 articles were examined to identify alleles associated with various diseases.

RESULTS

The analysis identified 117 alleles whose frequencies varied regionally within Mexico. While DPA1*01, DPB1*04:01, and DQA1*03 were predominant, DRB1*04, DQB1*03, and DQA1*05 were also prominent but variable. Certain alleles, such as A*02, B*35, C*04, and C*07, were relatively common in the population. Numerous disease correlations were uncovered, such as B*27's strong association with spondyloarthropathies. DRB1*15:01 and DRB1*04 conferred an increase in multiple sclerosis, while DRB1*04 may protect against some skin diseases.

CONCLUSION

This review improves the understanding of MHC allele frequencies and disease associations in Mexicans, highlighting genetic diversity. The findings lay the groundwork for future research on genetic predispositions and health outcomes, aiding healthcare strategies in this diverse population. Further studies are needed to address data gaps and refine genetic profiles for targeted medical applications.