CDKN2A and cerebral cavernous malformation: Ghiorzo et al. studied 49 CDKN2A-positive and 390 CDKN2A-negative Italian patients with CCM; MC1R variants were associated with increased odds of melanoma only in CDKN2A-negative patients, while first-degree family history of cutaneous melanoma increased the odds of developing melanoma in both variant-positive patients [40].