Question: the relationship between the roles of brca genes in dna repair and cancer predisposition

title: BRCA1
text: BRCA1 and BRCA2 are normally expressed in the cells of breast and other tissue , where they help repair damaged DNA , or destroy cells if DNA can not be repaired . They are involved in the repair of chromosomal damage with an important role in the error - free repair of DNA double - strand breaks . If BRCA1 or BRCA2 itself is damaged by a BRCA mutation , damaged DNA is not repaired properly , and this increases the risk for breast cancer . BRCA1 and BRCA2 have been described as `` breast cancer susceptibility genes '' and `` breast cancer susceptibility proteins '' . The predominate allele has a normal , tumor suppressive function whereas high penetrance mutations in these genes cause a loss of tumor suppressive function which correlates with an increased risk of breast cancer . 

Answer: answer: BRCA1 and BRCA2 are normally expressed in the cells of breast and other tissue, where they help repair damaged DNA, or destroy cells if DNA can not be repaired .
If BRCA1 or BRCA2 itself is damaged by a BRCA mutation, damaged DNA is not repaired properly, and this increases the risk for breast cancer.