Major histocompatibility complex (MHC) gene frequency in acquired dermal macular hyperpigmentation: a case control study

Abstract

BackgroundHuman leukocyte antigen (HLA) allele frequencies have a known association with the pathogenesis of various autoimmune diseases.MethodsWe recruited 31 Indian patients of acquired dermal macular hyperpigmentation (ADMH) and 60 unrelated, age‐and‐gender‐matched healthy controls. After history and clinical examination, 5 ml of blood in EDTA vials was collected. These samples were subjected to DNA extraction and the expression of HLA A, B, C, DR, DQ‐A, and DQ‐B was studied.ResultsThere was a predominance of females with a gender ratio of 23 : 8 and the most common phototype was Fitzpatrick type IV (83.9%). There was a significant association of HLA A*03:01 (OR: 5.8, CI: 1.7–17.0, P = 0.005), HLA B*07:02 (OR: 5.3, CI: 1.9–14.6, P = 0.003), HLA C*07:02 (OR: 4.3, CI: 1.8–9.6, P = 0.001), HLA DRB1*10:01 (OR: 7.6, CI: 1.7–38.00, P = 0.022), and HLA DRB1*15:02 (OR: 31.0, CI: 4.4–341.8, P < 0.001) with patients compared to controls, whereas HLA DQB*03:01 was less associated with patients compared to controls (OR: 0.2, CI: 0.0–0.6, P = 0.009).ConclusionPatients with ADMH are more likely to have the HLA A*03:01, HLA B 07*02, HLA C*07:02, HLA DRB1*10:01, HLA DRB1*15:02 and less likely to have the HLA DQB*03:01 allele. Larger cohort studies may thus be conducted studying these specific alleles.