sub:provenance { pmid:17236139dcterms:title "Mutations in CUL4B, which encodes a ubiquitin E3 ligase subunit, cause an X-linked mental retardation syndrome associated with aggressive outbursts, seizures, relative macrocephaly, central obesity, hypogonadism, pes cavus, and tremor" . sub:assertionhas-source:pmid:17236139 . }