However, while NF1 and SPRED1 mutations typically co-occur in cutaneous melanoma7,31, in our study of mucosal melanomas, most SPRED1 aberrations identified in WGS samples (11/13) occurred in NF1 wild-type samples, with only two SVs in SPRED1 co-occurring with NF1 mutations. Here, SPRED1 is linked to melanoma.