EGFR and alopecia: EGFR deletion or transgenic expression of a dominant-negative EGFR is lethal during embryonic development, but certain strains of mutant mice, which can survive several weeks, have severe skin abnormalities including epidermal atrophy, low epidermal keratinocyte proliferation rates, failure to develop a hairy coat or progressive alopecia and premature hair follicle differentiation [79–85].