| 2. |
- Johannsson, Oscar Thor, et al.
(författare)
-
Founding BRCA1 Mutations in Hereditary Breast and Ovarian Cancer in Southern Sweden
- 1996
-
Ingår i: American Journal of Human Genetics. - 0002-9297. ; 58:3, s. 441-450
-
Tidskriftsartikel (refereegranskat)abstract
- Nine different germ-line mutations in the BRCA1 breast and ovarian cancer susceptibility gene were identified in 15 of 47 kindreds from southern Sweden, by use of SSCP and heteroduplex analysis of all exons and flanking intron region and by a protein-truncation test for exon 11, followed by direct sequencing. All but one of the mutations are predicted to give rise to premature translation termination and include seven frameshift insertions or deletions, a nonsense mutation, and a splice acceptor site mutation. The remaining mutation is a missense mutation (Cys61Gly) in the zinc-binding motif. Four novel Swedish founding mutations were identified: the nucleotide 2595 deletion A was found in five families, the C 1806 T nonsense mutation in three families, the 3166 insertion TGAGA in three families, and the nucleotide 1201 deletion 11 in two families. Analysis of the intragenic polymorphism D17S855 supports common origins of the mutations. Eleven of the 15 kindreds manifesting BRCA1 mutations were breast-ovarian cancer families, several of them with a predominant ovarian cancer phenotype. The set of 32 families in which no BRCA1 alterations were detected included 1 breast-ovarian cancer kindred manifesting clear linkage to the BRCA1 region and loss of the wild-type chromosome in associated tumors. Other tumor types found in BRCA1 mutation/haplotype carriers included prostatic, pancreas, skin, and lung cancer, a malignant melanoma, an oligodendroglioma, and a carcinosarcoma. In all, 12 of 16 kindreds manifesting BRCA1 mutation or linkage contained ovarian cancer, as compared with only 6 of the remaining 31 families (P < .001). The present study confirms the involvement of BRCA1 in disease predisposition for a subset of hereditary breast cancer families often characterized by ovarian cancers.
|
|
| 3. |
- Shattuck Eidens, Donna, et al.
(författare)
-
A Collaborative Survey of 80 Mutations in the BRCA1 Breast and Ovarian Cancer Susceptibility Gene : Implications for Presymptomatic Testing and Screening
- 1995
-
Ingår i: JAMA: The Journal of the American Medical Association. - : American Medical Association (AMA). - 0098-7484. ; 273:7, s. 535-541
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES:To report the initial experience of an international group of investigators in identifying mutations in the BRCA1 breast and ovarian cancer susceptibility gene, to assess the spectrum of such mutations in samples from patients with different family histories of cancer, and to determine the frequency of recurrent mutations.DESIGN:Nine laboratories in North America and the United Kingdom tested for BRCA1 mutations in DNA samples obtained from a total of 372 unrelated patients with breast or ovarian cancer largely chosen from high-risk families. Three of these laboratories also analyzed a total of 714 additional samples from breast or ovarian cancer cases, including 557 unselected for family history, for two specific mutations that had been found to recur in familial samples.PARTICIPANTS:A total of 1086 women with either breast or ovarian cancer.MAIN OUTCOME MEASURE:The detection of sequence variation in patients' DNA samples that is not found in sets of control samples.RESULTS:BRCA1 mutations have now been identified in a total of 80 patient samples. Thirty-eight distinct mutations were found among 63 mutations identified through a complete screen of the BRCA1 gene. Three specific mutations appeared relatively common, occurring eight, seven, and five times, respectively. When specific tests for the two most common mutations were performed in larger sets of samples, they were found in 17 additional patients. Mutations predicted to result in a truncated protein accounted for 86% of the mutations detected by complete screening.CONCLUSIONS:The high frequency of protein-terminating mutations and the observation of many recurrent mutations found in a diverse set of samples could lead to a relatively simple diagnostic test for BRCA1 mutations. More data must be accumulated to address specifically the sensitivity and specificity of such a diagnostic testing procedure and to better estimate the age-specific risk for breast and ovarian cancer associated with such mutations.
|
|
