A total of 99 of these 118 patients (84%) had detectable ctDNA at baseline and on treatment, of whom 94 had mutations detected in one or more uveal melanoma genes (GNAQ, GNA11, SF3B1, PLCB4, CYSLTR2) at a variant allelic frequency of >0.3 at baseline and were included in the analyses (Methods, Table 1 and Supplementary Table 4). The gene discussed is GNAQ; the disease is uveal melanoma.