Objectives: To determine gene frequencies of HLA-DR alleles in 22 Mexican patients with focal epithelial hyperplasia and compare them with those present in ethnically matched healthy subjects, as well as to determine the types of human papillomavirus present in the lesions.
Design: Prospective and retrospective observational study.
Setting: Dermatology outpatient clinic in a general hospital.
Patients: Twenty-two patients with clinically and histologically confirmed focal epithelial hyperplasia seen within a 10-year period.
Interventions: None.
Main outcome measures: Results of high-resolution DNA typing for HLA-DR alleles and biopsy for viral typing.
Results: HLA-DR4 (DRB1*0404) was significantly increased (P<.001; odds ratio, 3.9; 95% confidence interval, 1.86-8.03). Seventeen (85%) of 20 patients had human papillomavirus subtype 13. The data on human papillomavirus differed from reports elsewhere that described association with human papillomavirus type 32.
Conclusions: The HLA-DRB1*0404 allele suggests that Amerindian populations are at risk, and in this group, the Mexican population studied was affected only by human papillomavirus type 13.