Objective: To study the BRCA1/2 gene mutation frequency and characteristics in Chinese familial breast cancer patients.
Methods: Denaturing high-performance liquid chromatography (DHPLC) and following DNA sequencing in BRCA1/2 gene whole coding region and exon-intron splicing sites were performed in the specimens obtained during operation from 115 probands of familial breast cancer from 4 breast cancer centers in China.
Results: Fourteen cases of gene mutation (11 in BRCA1 and 3 in BRCA2) were found in the 115 breast cancer specimens with an overall mutation rate of 12.2%. After stratification with number of breast cancer patients in family, the frequency of mutation did not change significantly. The average age of disease onset of the families carrying BRCA1/2 mutations was significantly younger than that of the families without mutations (P < 0.01), and the higher the number of young patients in family, the higher the mutation rate.
Conclusion: In Chinese familial breast cancer patients, age of disease-onset is an effective predictive factor of BRCA1/2 mutation, however, the predictive effect of the number of affective relatives in family is not good.