In particular, in three patients presenting with mild, adult-onset disease we found variants (PROKR2 R85H, FGF8 P26L, and HS6ST1 R382W) already reported to impair protein activity in several functional characterization or to segregate with the phenotype, or both [26,27,28,29,30,31,32,33]. This evidence concerns the gene PROKR2 and Onset.