These results, together with the finding that endogenous sPLA2-X shows a hair cycle-dependent periodic expression in the outer root sheath of hair follicles in mouse skin (Figure 2e) [38], suggest a potential functional link between sPLA2-X and skin biology, and may provide a molecular explanation for the skin abnormality induced by aberrant expression of other sPLA2s such as sPLA2-IIA, whose transgenic mice also developed alopecia [39]. Here, PLA2G10 is linked to alopecia.