KCTD15 and scalp-ear-nipple syndrome: Intriguingly, however, heterozygous missense variants in the BTB domain of KCTD1, which encodes the closest human paralogue of KCTD15, cause SEN syndrome, which exhibits a partially overlapping phenotype including cutis aplasia of the scalp.19 20 This provided additional circumstantial support that the KCTD15 variant could be pathogenic in Family 1.