Ubiquitous. NSUN5P1 is located in the Williams-Beuren syndrome (WBS) critical region. WBS results from a hemizygous deletion of several genes on chromosome 7q11.23, thought to arise as a consequence of unequal crossing over between highly homologous low-copy repeat sequences flanking the deleted region. Belongs to the class I-like SAM-binding methyltransferase superfamily. RsmB/NOP family. Could be the product of a pseudogene.