Association of HLA-DR3 and HLA-DR4 with Sinonasal Polyposis in Mexican Mestizos

Objective The pathogenesis of sinonasal polyposis (SNP) is not clear; it has been suggested that it is polygenic and multifactorial. The major histocompatibility complex is a useful tool to predict genetic susceptibility to diseases, especially to autoimmune diseases. Since such susceptibility is influenced by ethnicity, it is necessary to have a wide knowledge of the structure of the population to which the patient belongs. The purpose of the study was to determine the association of HLA-DRB1 alleles with sinonasal polyposis in the Mexican Mestizo population. Study design We studied the HLA-DR alleles in 34 adult Mexican Mestizo patients with SNP and compared them to those present in 99 healthy controls. Methods Genomic DNA from mononuclear cells was obtained by using the “salting out” technique and high-resolution DNA typing of the HLA-DRB1 alleles was performed after PCR amplification. Results We found a statistically significant increased frequency of the HLA-DRB1*03 allele ( P = 0.03, odds ratio [OR] = 2.9, 95% confidence interval [CI]: 1.0-7.8) and of the HLA-DRB1*04 allele ( P = 0.009, OR = 2.2, 95% CI: 1.2-4.2) in patients with SNP as compared to controls, and a statistically significant decreased frequency of the HLA-DRB1*08 allele ( P = 0.01, OR = 0.2, 95% CI: 0.05-0.8). Conclusion The HLA-DR locus seems to be associated with the genetic susceptibility to develop SNP in Mexicans. EBM rating: B-2b