Angelman syndrome associated with oculocutaneous albinism due to an intragenic deletion of the P gene
Article first published online: 8 MAY 2003
Copyright © 2003 Wiley-Liss, Inc.
American Journal of Medical Genetics Part A
Volume 119A, Issue 2, pages 180–183, 1 June 2003
How to Cite
Fridman, C., Hosomi, N., Varela, M.C., Souza, A.H., Fukai, K. and Koiffmann, C.P. (2003), Angelman syndrome associated with oculocutaneous albinism due to an intragenic deletion of the P gene. Am. J. Med. Genet., 119A: 180–183. doi: 10.1002/ajmg.a.20105
- Issue published online: 8 MAY 2003
- Article first published online: 8 MAY 2003
- Manuscript Accepted: 1 OCT 2002
- Manuscript Received: 26 JUN 2001
- Ministry of Education, Science, and Culture of Japan. Grant Number: 13670897
- Osaka City University Medical Research Foundation
- P gene;
- Angelman syndrome
Angelman syndrome (AS) is a neurodevelopmental disorder characterized by mental retardation, speech impairment, ataxia, and happy disposition with frequent smiling. AS results from the loss of expression of a maternal imprinted gene, UBE3A, mapped within 15q11-q13 region, due to different mechanisms: maternal deletion, paternal UPD, imprinting center mutation, and UBE3A mutation. Deletion AS patients may exhibit hypopigmentation of skin, eye, and hair correlating with deletion of P gene localized in the distal part of Prader-Willi (PWS)/AS region. Our patient presented developmental delay, severe mental retardation, absence of speech, outbursts of laughter, microcephaly, ataxia, hyperactivity, seizures, white skin, no retinal pigmentation, and gold yellow hair. His parents were of African ancestry. The SNURF-SNRPN methylation analysis confirmed AS diagnosis and microsatellite studies disclosed deletion with breakpoints in BP2 and BP3. All of the 25 exons and flanking introns of the P gene of the patient, his father, and mother were investigated. The patient is hemizygous for the deleted exon 7 of the P gene derived from his father who is a carrier of the deleted allele. Our patient manifests OCA2 associated with AS due to the loss of the maternal chromosome 15 with the normal P allele, and the paternal deletion in the P gene. As various degrees of hipopygmentation are associated with PWS and AS patients, the study of the P gene in a hemizygous state could contribute to the understanding of its effect on human pigmentation during development and to disclose the presence of modifier pigmentation gene(s) in the PWS/AS region. © 2003 Wiley-Liss, Inc.