POC1A and Marinesco-Sjogren syndrome: Given that mutations in POC1A are causative for SOFT (short stature, onychodysplasia, facial dysmorphism, and hypotrichosis) syndrome (22) and short stature is also a clinical finding in MSS patients, a regulatory effect of abundances of the SIL1-wildtype protein on level of POC1A was confirmed by immunoblot studies.