NOP2/Sun Domain Family, Member 5 (NSUN5)

NSUN5 encodes a member of the evolutionarily conserved NOL1/NOP2/Sun domain family. This gene is deleted in Williams syndrome, a multisystem developmental disorder caused by the deletion of contiguous genes at 7q11.23. Alternative splicing of this gene results in multiple transcript variants encoding different isoforms. WBSCR20 encodes a novel protein expressed in skeletal muscle with similarity to p120 (NOL1), a 120-kDa proliferation-associated nucleolar antigen, a member of an evolutionarily conserved protein family. A highly similar putative gene, WBSCR20B, flanks the WBS deletion at the telomeric side. Hemizygous deletion of either of the novel genes might contribute to the growth retardation, the myopathy or the premature aging effects in the pathogenesis of WBS.