SnapshotDx Quiz: August 2019

In 2019, Hochfeld et al. conducted a study on male androgenetic alopecia (AGA), the most common cause of hair loss in men. The study, which involved 24 male human donors, found that AGA is androgen-dependent and highly heritable, typically presenting with gradual hair loss from the frontotemporal and vertex of the scalp. The main pathogenic mechanisms in AGA were identified as androgen-induced follicular miniaturization and premature catagen entry due to a shortened anagen phase. The study also revealed differential expression of microRNAs and mRNAs in plucked hair follicles, with most microRNAs showing higher expression and most mRNAs showing lower expression in frontal hair follicles. Six previously unreported gene regions for AGA were identified. The study also found a significant relationship between the AGA risk allele and increased expression of RORA, a gene involved in hair density and regrowth. Despite identifying over 300 genome-wide significant AGA risk variants, their functional effects on AGA's pathogenesis remained unclear.