BRCA1/2 Germline Gene Mutation In 43 Cases Of Breast Cancer

Objective:To analyze the BRCA1/2 gene exon region in 43 breast cancer patients,analyze the mutation status of BRCA1/2 gene in breast cancer patients,and compare the differences in clinical characteristics.Methods:This study enrolled 43 breast cancer patients who had undergone BRCA1/2gene testing between 2017 and 2019,and compared the clinical characteristics of BRCA1/2 mutation-positive and mutation-negative patients.Results:1.Among 43 breast cancer patients,10 patients carried the pathogenic germline mutation of the BRCA1/2 gene,with a total mutation rate of 23.26%(10/43).Among these 10 patients,6 patients carried BRCA1 gene mutation,the mutation rate was 13.95%(6/43),4 patients carried the BRCA2 gene mutation,the mutation rate was 9.3%(4/43).2.In addition to pathogenic germline mutations,two unidentified mutations were found in this study,namely c.5402G> A and c.3334G> T.More research and longer follow-up are needed to clarify these unknown mutations.3.Compared with the non-mutated group in the age of the BRCA1/2 pathogenic mutation group,the diagnosis age of the mutation-negative individuals was slightly larger than that of the mutation-positive individuals,however,the difference was not significant(P = 0.616).4.Comparing the pathogenic mutations of BRCA1/2 gene with and without family history,the difference was statistically significant(P = 0.00001).5.Two pathogenic mutation sites(BRCA1 c.6076delA;BRCA1c.9069＿9076delTAACATAC)newly discovered in this study have not been reported in ClinVar,BRCA Exchange and other databases,which may be unique to Chinese and enrich the Chinese population BRCA1 And BRCA2 gene mutation profiles.Genetic screening of other healthy pedigree members in the family carrying the disease-causing mutation gene,site-specific monitoring of the disease-causing mutation site,accurate follow-up and understanding of the disease risk of all family members are the key points of preventive intervention.6.Four patients in the total sample carried the same pathogenic mutation as BRCA1 c.5470＿5477delATTGGGCA.The mutation was detected in multiple Chinese families of hereditary breast and / or ovarian cancer patients or early-onset triple-negative breast cancer patients,which is presumed to be a ancestral disease unique to the BRCA1 gene in the Chinese population,and family hereditary breast and Related to carcinogenesis and development.Conclusion:1.This study analyzed the clinical characteristics of patients with familial and sporadic breast cancer,and found that there was no statistical difference in age between those with BRCA1/2 mutations and those without mutations.2.The proportion of breast cancer family history in BRCA1/2 gene mutation is higher than sporadic population.It is recommended that people with family history be screened for BRCA1/2 gene.3.This study identified two newly discovered pathogenic mutation sites(BRCA2c.6076delA;c.9069＿9076delTAACATAC),which enriched the mutation lineage,and had a significant impact on breast cancer genetic risk and prognosis.The impact needs further verification.4.BRCA1 c.5470＿5477del ATTGGGCA was detected in patients with hereditary breast cancer and / or ovarian cancer or early-onset triple-negative breast cancer in multiple Chinese families.It is presumed to be the progenitor lesion unique to the BRCA1 gene in the Chinese population,and family inheritance The development of breast cancer and ovarian cancer is related.