Novel TP53 gene mutations in tumors of Russian patients with breast cancer detected using a new solid phase chemical cleavage of mismatch method and identified by sequencing.
Hum Mutat
; 23(2): 186-192, 2004 Feb.
Article
en En
| MEDLINE
| ID: mdl-14722922
ABSTRACT
Mutations in the tumor-suppressor p53 gene TP53 are frequent in most human cancers including breast cancer. A new solid phase chemical cleavage of mismatch method (CCM) allowed rapid and efficient screening and analysis of the TP53 gene in DNA samples extracted from tumors of 89 breast cancer patients. The novel CCM technique utilized silica beads and the potassium permanganate/tetraethylammonium chloride (KMnO(4)/TEAC) and hydroxylamine (NH(2)OH) reactions were performed sequentially in a single tube. Mutation analysis involved amplification of five different fragments of the TP53 gene using DNA from the 89 tumor samples, then pairing of the 391 labeled PCR products and forming heteroduplexes. A total of 41 unique signals were revealed in the analysis of TP53 exons 5-9 and eight were identified by direct sequencing. The three novel mutations detected are c.600T>G (p.Asn200Lys), c.601T>G (p.Leu201Val), and c.766-768delACA (p.Thr256del). The detected mutations c.638G>T (p.Arg213Leu), c.730G>T (p.Gly244Cys), and c.758C>T (p.Thr253Ile) have not been reported in breast cancer but have been recorded in tumors of other organs. A previously reported mutation c.535C>T (p.His179Tyr) and a heterozygous polymorphism c.639A>G were also detected. Of the 41 unique signals, 36 were not identified as a sequence change. As direct sequencing requires the mutant allele concentration to be greater than 30% when the mutant allele is present in a mixture with the wild-type allele, the CCM method represents a more sensitive technique requiring a lower mutant allele concentration in the wild-type mixture compared with direct sequencing. This reveals the advantage of CCM for unknown point mutation detection in DNA samples of cancer patients.
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Neoplasias de la Mama
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Análisis Mutacional de ADN
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Genes p53
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Disparidad de Par Base
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Mutación
Límite:
Adult
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Aged
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Female
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Humans
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Middle aged
País/Región como asunto:
Asia
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Europa
Idioma:
En
Revista:
Hum Mutat
Asunto de la revista:
GENETICA MEDICA
Año:
2004
Tipo del documento:
Article
País de afiliación:
Australia