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Title: Early embryonic failure: Expression and imprinted status of candidate genes on human chromosome 21

Abstract

Two cases of maternal uniparental (hetero)disomy for human chromosome 21 (mUPD21) have been identified in a systematic search for UPD in 23 cases of early embryonic failure (EEF). Bi-parental origin of the other chromosome pairs was confirmed using specific VNTR probes or dinucleotide repeat analysis. Both maternally and paternally derived isochromosomes 21q have previously been identified in two individuals with normal phenotypes. Full UPD21 has a different mechanism of origin than uniparental isochromosome 21q and its effect on imprinted genes and phenotypic outcome will therefore not necessarily be the same. EEF associated with mUPD21 suggests that developmentally important genes on HSA 21 may be imprinted such that they are only expressed from either the maternally or paternally derived alleles. We have searched for monoallelic expression of candidate genes on HSA 21 in human pregnancy (CBS, IFNAR, COL6A1) using intragenic DNA polymorphisms. These genes were chosen either because their murine homologues lie in imprinted regions or because they are potentially important in embryogenesis. Once imprinted candidate genes have been identified, their methylation status and expression in normal, early embryonic failure and uniparental disomy 21 pregnancies will be studied. At the same time, a larger number of cases of EEF are beingmore » examined to further investigate the incidence of UPD21 in this group.« less

Authors:
; ;  [1]
  1. Queen Charlotte`s and Chelsea Hospital, London (United Kingdom)
Publication Date:
OSTI Identifier:
134505
Report Number(s):
CONF-941009-
Journal ID: AJHGAG; ISSN 0002-9297; TRN: 95:005313-1239
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; EMBRYOS; ABORTION; ONTOGENESIS; HUMAN CHROMOSOME 21; CHROMOSOMAL ABERRATIONS; GENES; GENE REGULATION; METHYLATION; PATIENTS; HEREDITARY DISEASES; PHENOTYPE; GENETICS; PROBES; NUCLEOTIDES

Citation Formats

Sherman, L.S., Bennett, P.R., and Moore, G.E. Early embryonic failure: Expression and imprinted status of candidate genes on human chromosome 21. United States: N. p., 1994. Web.
Sherman, L.S., Bennett, P.R., & Moore, G.E. Early embryonic failure: Expression and imprinted status of candidate genes on human chromosome 21. United States.
Sherman, L.S., Bennett, P.R., and Moore, G.E. 1994. "Early embryonic failure: Expression and imprinted status of candidate genes on human chromosome 21". United States. doi:.
@article{osti_134505,
title = {Early embryonic failure: Expression and imprinted status of candidate genes on human chromosome 21},
author = {Sherman, L.S. and Bennett, P.R. and Moore, G.E.},
abstractNote = {Two cases of maternal uniparental (hetero)disomy for human chromosome 21 (mUPD21) have been identified in a systematic search for UPD in 23 cases of early embryonic failure (EEF). Bi-parental origin of the other chromosome pairs was confirmed using specific VNTR probes or dinucleotide repeat analysis. Both maternally and paternally derived isochromosomes 21q have previously been identified in two individuals with normal phenotypes. Full UPD21 has a different mechanism of origin than uniparental isochromosome 21q and its effect on imprinted genes and phenotypic outcome will therefore not necessarily be the same. EEF associated with mUPD21 suggests that developmentally important genes on HSA 21 may be imprinted such that they are only expressed from either the maternally or paternally derived alleles. We have searched for monoallelic expression of candidate genes on HSA 21 in human pregnancy (CBS, IFNAR, COL6A1) using intragenic DNA polymorphisms. These genes were chosen either because their murine homologues lie in imprinted regions or because they are potentially important in embryogenesis. Once imprinted candidate genes have been identified, their methylation status and expression in normal, early embryonic failure and uniparental disomy 21 pregnancies will be studied. At the same time, a larger number of cases of EEF are being examined to further investigate the incidence of UPD21 in this group.},
doi = {},
journal = {American Journal of Human Genetics},
number = Suppl.3,
volume = 55,
place = {United States},
year = 1994,
month = 9
}
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