In one vfDNA+/UM− patient, the primary uveal melanoma was known to carry two clonally-abundant Gαq signalling mutations (GNA11 p.R183H and PLCB4 p.D630N in vfDNA-29), but the vfDNA only contained wild-type GNA11 and PLCB4 in comparable concentrations (Supplementary Fig. 1D). Here, PLCB4 is linked to uveal melanoma.