Publication Date:
1991-06-21
Description:
The sequence of a Pst I restriction fragment was determined that demonstrate instability in fragile X syndrome pedigrees. The region of instability was localized to a trinucleotide repeat p(CCG)n. The sequence flanking this repeat were identical in normal and affected individuals. The breakpoints in two somatic cell hybrids constructed to break at the fragile site also mapped to this repeat sequence. The repeat exhibits instability both when cloned in a nonhomologous host and after amplification by the polymerase chain reaction. These results suggest variation in the trinucleotide repeat copy number as the molecular basis for the instability and possibly the fragile site. This would account for the observed properties of this region in vivo and in vitro.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kremer, E J -- Pritchard, M -- Lynch, M -- Yu, S -- Holman, K -- Baker, E -- Warren, S T -- Schlessinger, D -- Sutherland, G R -- Richards, R I -- New York, N.Y. -- Science. 1991 Jun 21;252(5013):1711-4.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Cytogenetics and Molecular Genetics, Adelaide Children's Hospital, South Australia.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/1675488" target="_blank"〉PubMed〈/a〉
Keywords:
Base Sequence
;
Blotting, Southern
;
Chromosome Mapping
;
Fragile X Syndrome/*genetics
;
Humans
;
Molecular Sequence Data
;
Pedigree
;
Polymerase Chain Reaction
;
Polymorphism, Restriction Fragment Length
;
Repetitive Sequences, Nucleic Acid
;
Restriction Mapping
;
X Chromosome/ultrastructure
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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