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Title: APC-like congenital hypertrophy of the retinal pigment epithelium (CHRPE) in non-APC patients: Evidence for autosomal dominant transmission in one family

Abstract

The presence of congenital hypertrophy of the retinal pigment epithelium (CHRPE) is known to be the earliest phenotypic marker in carriers of a mutant allele of the adenomatous polyposis coli gene (APC). The specificity of CHRPE is known to be over 97%, provided that the lesions are bilateral and their total number higher than 4. In the present study, we describe 3 patients from 2 unrelated families with bilateral multiple asymptomatic CHRPE (8-17), normal visual function and no family history of APC. Clinical examination failed to detect other extracolonic signs of APC nor did a search for adenomatous polyps by colonscopy. In one family, the ocular phenotype was transmitted from a father to his only son. Mutation hot spots at codons 302, 622, 625, 1061 and 1309 of the APC gene (about 25% of germline mutations) were all tested normal. We postulate that these APC-free ocular findings reflect the allelic involvement of a mutant APC allele that remains to be characterized. However, involvement of another yet unrecognized autosomal dominant gene cannot be ruled out and additional families with this unique trait should be studied.

Authors:
;  [1]
  1. Universite de Lausanne (Switzerland) [and others
Publication Date:
OSTI Identifier:
133585
Report Number(s):
CONF-941009-
Journal ID: AJHGAG; ISSN 0002-9297; TRN: 95:005313-0314
Resource Type:
Journal Article
Resource Relation:
Journal Name: American Journal of Human Genetics; Journal Volume: 55; Journal Issue: Suppl.3; Conference: 44. annual meeting of the American Society of Human Genetics, Montreal (Canada), 18-22 Oct 1994; Other Information: PBD: Sep 1994
Country of Publication:
United States
Language:
English
Subject:
55 BIOLOGY AND MEDICINE, BASIC STUDIES; GENES; GENE MUTATIONS; PATIENTS; CONGENITAL DISEASES; PHENOTYPE; SENSE ORGANS DISEASES; DIGESTIVE SYSTEM DISEASES; EPITHELIUM; GENETICS; DOMINANT MUTATIONS

Citation Formats

Thonney, E., and Munier, F.L. Pescia, G.. APC-like congenital hypertrophy of the retinal pigment epithelium (CHRPE) in non-APC patients: Evidence for autosomal dominant transmission in one family. United States: N. p., 1994. Web.
Thonney, E., & Munier, F.L. Pescia, G.. APC-like congenital hypertrophy of the retinal pigment epithelium (CHRPE) in non-APC patients: Evidence for autosomal dominant transmission in one family. United States.
Thonney, E., and Munier, F.L. Pescia, G.. 1994. "APC-like congenital hypertrophy of the retinal pigment epithelium (CHRPE) in non-APC patients: Evidence for autosomal dominant transmission in one family". United States. doi:.
@article{osti_133585,
title = {APC-like congenital hypertrophy of the retinal pigment epithelium (CHRPE) in non-APC patients: Evidence for autosomal dominant transmission in one family},
author = {Thonney, E. and Munier, F.L. Pescia, G.},
abstractNote = {The presence of congenital hypertrophy of the retinal pigment epithelium (CHRPE) is known to be the earliest phenotypic marker in carriers of a mutant allele of the adenomatous polyposis coli gene (APC). The specificity of CHRPE is known to be over 97%, provided that the lesions are bilateral and their total number higher than 4. In the present study, we describe 3 patients from 2 unrelated families with bilateral multiple asymptomatic CHRPE (8-17), normal visual function and no family history of APC. Clinical examination failed to detect other extracolonic signs of APC nor did a search for adenomatous polyps by colonscopy. In one family, the ocular phenotype was transmitted from a father to his only son. Mutation hot spots at codons 302, 622, 625, 1061 and 1309 of the APC gene (about 25% of germline mutations) were all tested normal. We postulate that these APC-free ocular findings reflect the allelic involvement of a mutant APC allele that remains to be characterized. However, involvement of another yet unrecognized autosomal dominant gene cannot be ruled out and additional families with this unique trait should be studied.},
doi = {},
journal = {American Journal of Human Genetics},
number = Suppl.3,
volume = 55,
place = {United States},
year = 1994,
month = 9
}
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