Insights into the biological differences in hair follicles of men with androgenetic alopecia

. Androgenetic alopecia (AGA) is a condition that leads to balding, mainly of the front and top of the head. AGA affects around half of all men worldwide and can have a great impact on their appearance and social life. Hair grows in hair follicles (HFs), and goes through phases of growth, transition and resting. We carried out a type of study called a ‘whole transcriptome analysis’ of HFs from people with AGA. Our team in China compared the HFs from balding and non-balding areas of 10 men to determine their different genetic makeups in terms of three types of RNA (messenger RNA, microRNA and long non-coding RNA). We identiﬁed 688 RNA contents that were expressed differently in HFs from balding and non-balding areas. We found four path-ways that were expressed differently, but focused on two: called the hypoxia-inducible factor (HIF)-1 signalling pathway and the Wnt signalling pathway. We also conﬁrmed that HIF-1 pathway-related genes ( EGLN1 , EGLN3 ) and Wnt pathway inhibitors ( SERPINF1 , SFRP2 ) play important roles in dermal papilla cell activity, hair growth and the hair cycle. The EGLN1 , EGLN3 , SERPINF1 and SFRP2 genes may therefore potentially be used as targets for treatment of AGA. Our ﬁndings should be a valuable resource for future studies into AGA and treatments for hair loss.