title: The prevalence of BRCA1 and BRCA2 mutations in eastern Chinese women with breast cancer.
abstract: To investigate the prevalence of BRCA1 and BRCA2 mutations among Chinese patients, we studied 70 Shanghai cases with early onset breast cancer and affected relatives, and mutation screening was performed in the whole-gene sequence of BRCA1 and BRCA2 by polymerase chain reaction-based denaturing high-performance liquid chromatography. Six disease-causing mutations in BRCA1 (8.6%) and two in BRCA2 (2.9%) were detected, including four novel mutations that were all in the BRCA1 gene (3449insA, IVS17-1G>T, IVS21+1G>C and 5587-1del8). Additional sequence variants identified included 30 polymorphisms (18 in BRCA1 and 12 in BRCA2) and a novel mis-sense mutation of unknown significance in BRCA2 (5911G>C). The 9.5 and 2.4% patients with breast cancer diagnosed before the age of 35 were BRCA1- and BRCA2-mutation carriers, and the prevalence of BRCA1 and BRCA2 mutations in the families with two or more affected individuals were 12.1 and 3.0%, respectively. In these families, all the BRCA1 and BRCA2 mutations were detected in the families containing at least one case diagnosed under the age of 40, and in the families whose youngest patients were diagnosed before the age of 35, the prevalence of BRCA1 and BRCA2 were as high as 40 and 20%, respectively. Based on this information, we conclude that genetic testing should be performed among patients with early onset breast cancer (<40 years), especially combined with family history.
authors.affiliation: Department of Breast Surgery, Breast Cancer Institute, Cancer Hospital/Cancer Institute, Fudan University, 399 Ling-Ling Road, Shanghai, 200032, People's Republic of China.
authors.forename: Chuan-Gui
authors.initials: CG
authors.lastname: Song
authors.forename: Zhen
authors.initials: Z
authors.lastname: Hu
authors.forename: Jiong
authors.initials: J
authors.lastname: Wu
authors.forename: Jian-Min
authors.initials: JM
authors.lastname: Luo
authors.forename: Zhen-Zhou
authors.initials: ZZ
authors.lastname: Shen
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Zhi-Ming
authors.initials: ZM
authors.lastname: Shao
mesh_terms: D000328:Adult; D044466:Asian People / Q000235:genetics; D019313:BRCA1 Protein / Q000235:genetics*; D024682:BRCA2 Protein / Q000235:genetics*; D001483:Base Sequence; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000208:ethnology; D002681:China; D004252:DNA Mutational Analysis; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008875:Middle Aged; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D011110:Polymorphism, Genetic; D015995:Prevalence
chemical_list: D019313:BRCA1 Protein; D024682:BRCA2 Protein