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Title: {open_quotes}Unspecific{close_quotes} X-linked mental retardation: Clinical, genetic and molecular studies

Abstract

Previous linkage studies have assigned a gene for non-syndromic X-linked mental retardation (XMR) to at least 8 different regions on the X-chromosome. The fragile X-syndrome (FRAXA) does not account for more than 40% of all cases; in most XMR families early diagnosis and prevention is not possible. As part of a systematic study into {open_quotes}unspecific{close_quotes} XMR involving more than 30 non-FRAXA families, linkage studies have enabled us to map the respective genes in 4 families to the Xp11.4-q12 interval with peak lod scores around the ALAS2 locus. In three other families, the gene defect could be assigned to the KAL-DMD, DXS424-FRAXAC2 and DSX52-Xqter intervals, respectively. In one of these families, small stature due to growth hormone deficiency was observed as a distinctive clinical feature. Molecular cloning of the breakpoint in a mentally retarded girl with a balanced t(Xq13;13q) translocation has enabled us to isolate an X-chromosomal gene which is disrupted in this patient and is highly expressed in brain. YAC cloning strategies are being employed to clone another XMR gene, which has been identified previously in the vicinity of the CHM locus and genes involved in mentally retarded patients with two different inversions, inv(X)(q21p11) and inv(X)(p21q24), respectively.

Authors:
; ;  [1]
  1. University Hospital, Nijmegen (Netherlands); and others
Publication Date:
OSTI Identifier:
133459
Report Number(s):
CONF-941009-
Journal ID: AJHGAG; ISSN 0002-9297; TRN: 95:005313-0187
Resource Type:
Journal Article
Journal Name:
American Journal of Human Genetics
Additional Journal Information:
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; HUMAN X CHROMOSOME; GENETIC MAPPING; CHROMOSOMAL ABERRATIONS; PATIENTS; MENTAL DISORDERS; GENES; GROWTH; INHIBITION; GENETICS; DNA-CLONING; STH; YEASTS; STATISTICS

Citation Formats

Ropers, H H, Maacel, S van der, and Knoers, N. {open_quotes}Unspecific{close_quotes} X-linked mental retardation: Clinical, genetic and molecular studies. United States: N. p., 1994. Web.
Ropers, H H, Maacel, S van der, & Knoers, N. {open_quotes}Unspecific{close_quotes} X-linked mental retardation: Clinical, genetic and molecular studies. United States.
Ropers, H H, Maacel, S van der, and Knoers, N. 1994. "{open_quotes}Unspecific{close_quotes} X-linked mental retardation: Clinical, genetic and molecular studies". United States.
@article{osti_133459,
title = {{open_quotes}Unspecific{close_quotes} X-linked mental retardation: Clinical, genetic and molecular studies},
author = {Ropers, H H and Maacel, S van der and Knoers, N},
abstractNote = {Previous linkage studies have assigned a gene for non-syndromic X-linked mental retardation (XMR) to at least 8 different regions on the X-chromosome. The fragile X-syndrome (FRAXA) does not account for more than 40% of all cases; in most XMR families early diagnosis and prevention is not possible. As part of a systematic study into {open_quotes}unspecific{close_quotes} XMR involving more than 30 non-FRAXA families, linkage studies have enabled us to map the respective genes in 4 families to the Xp11.4-q12 interval with peak lod scores around the ALAS2 locus. In three other families, the gene defect could be assigned to the KAL-DMD, DXS424-FRAXAC2 and DSX52-Xqter intervals, respectively. In one of these families, small stature due to growth hormone deficiency was observed as a distinctive clinical feature. Molecular cloning of the breakpoint in a mentally retarded girl with a balanced t(Xq13;13q) translocation has enabled us to isolate an X-chromosomal gene which is disrupted in this patient and is highly expressed in brain. YAC cloning strategies are being employed to clone another XMR gene, which has been identified previously in the vicinity of the CHM locus and genes involved in mentally retarded patients with two different inversions, inv(X)(q21p11) and inv(X)(p21q24), respectively.},
doi = {},
url = {https://www.osti.gov/biblio/133459}, journal = {American Journal of Human Genetics},
number = Suppl.3,
volume = 55,
place = {United States},
year = {Thu Sep 01 00:00:00 EDT 1994},
month = {Thu Sep 01 00:00:00 EDT 1994}
}