In a healthy body cells grow and divide normally, that is only when body needs extra cell for the proper functioning of the body. Sometimes the cell growth regulatory mechanism stops working properly, and cells starts to divide continuously to form tumors. These types of tumors are called as cancer. When these continuous cell growth occur in cells present in the breast are known as breast cancer. If the same kind of cancer is seen in the cells of the ovarian tissue then it is called as ovarian cancer. Only a small percent of breast and ovarian cancer are caused by the genetics which are inherited by the parents. These cases are as a result of inherited mutated form of either BRCA1 or BRCA2 genes.

How do we get Breast or Ovarian Cancer?

The genes BRCA1 and BRCA2 are tumor suppressor genes, that is normal BRCA1 and BRCA2 genes control the cell growth and division of an organism. BRCA1 gene is present on chromosome 17, and BRCA2 gene is present on chromosome 13. Researchers and scientists believe that these two genes are involved in repairing damaged or broken DNA molecule. Damaged and broken DNA molecules are accumulated in women who have inherited the mutated copy of the gene BRCA1 or BRCA2. This accumulation if damaged DNA molecules in the cell increases the possibility of uncontrolled cell division and tumor or cancer formation. Not only women but the men who have inherited the mutated form of these two genes are also more prone to breast cancer or/and prostate cancer.

Individuals who have inherited the mutated form of gene BRCA1 or BRCA2 are more prone to breast or ovarian cancer. Dominant form of mutations is seen in these two genes, that is only one copy of mutated gene is sufficient to increase the risk of cancer. Children have 50 percent of chance of inheriting the mutation, if one of the parents has a mutated form of BRCA1 or BRCA2.

If the mutated form of gene is present in an individual does not indicate that he/she will develop cancer, but inheritance of these two mutated form of gene increases the risk of getting cancer. For example in 100 women who have inherited the mutated form of gene BRCA1 and BRCA2, only 60 will develop breast cancer in their 50s.

How do we get Colon Cancer?

Uncontrolled cell growth and division occur in the cells lining colon will lead to the formation of colon cancer. Individuals who have inherited any one of the two genetic conditions, such as FAP (familial adenomatous polyposis) or HNPCC (hereditary non-polyposis colon cancer) are at high risk of developing colon cancer.

Mutation of the gene APC (adenomatous polyposis coli) on chromosome 5 leads to FAP. Tumor suppressor gene APC controls the cell growth. Mutated form of APC gene leads to growths known as polyps in the colon. If these polyps are not treated at the early stage, they will convert into colon cancer.

Mutations in the genes involved in DNA repair leads to the condition known as HNPCC. Individuals with HNPCC will accumulate damaged DNA in their cell and this will lead to the cancer.

Both HNPCC and APC mutations are dominant form, that is only one copy of mutated genes are sufficient to increase the risk of colon cancer.


Researchers can design efficient pharmaceutical agent or drug and can also discover new novel therapy to treat cancer, by understanding the genes or genetics of the cancer.

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