Abstract
BACKGROUND: Vitiligo and freckles are both pigmentary disorders of the skin. The high prevalence of these conditions also places substantial strain on social healthcare systems. While vitiligo shows genetic predisposition, freckles exhibit autosomal dominant inheritance. Both conditions are closely linked to the immune system, potentially involving immune irregularities and autoimmune deficiencies. OBJECTIVE: This study aimed to investigate the correlation between vitiligo and freckles in relation to major histocompatibility complex (MHC) regions to better understand the genetic factors influencing these chronic pigmentation disorders. METHODS: Data from 3315 vitiligo patients, 7168 healthy controls, 524 freckle patients, and 4280 healthy controls were collected. A genome-wide association study (GWAS) utilizing the Infinium Global Screening Array-24 v2.0 BeadChip (GSA) and MHC region imputation was conducted, followed by meta-analysis. RESULTS: Through stepwise conditional analysis, five single-nucleotide polymorphisms (SNPs) associated with both vitiligo and freckles were identified. These genetic markers shed light on common susceptibility factors between the two diseases. CONCLUSION: The findings of this study provide insights into the genetic basis of vitiligo and freckles, suggesting potential associations and shared pathways. Understanding these genetic correlations can aid in disease diagnosis, prevention strategies, and further exploration of biological mechanisms underlying these pigmentation disorders.