While CDKN2A gene knockout in mice is associated with oligozoospermia, propensity to skin tumours including fibrosarcomas and haematological malignancies (Blake et al., 2021) Little is known about FMS, however the recognised clinical phenotype is of multiple melanocytic naevi (usually >50, many of which are atypical), early onset melanoma and pancreatic carcinoma (Mize et al., 2009). Here, CDKN2A is linked to melanoma.