Somatic Mutation and Germline Mutation in Cancer


Are genes related to the development of a cancer?

Oncogenes are mutated genes that lead to uncontrollable cell growth and cancers. Mutated HER2 is one of the example, which play a role in developing cancer such as breast cancers.

Tumour suppressor genes are responsible for taming abnormal cell growth. They act as a braking system to stop the cell from out-of-control multiplying. Mutations in tumour suppressor genes can disrupt its regulation or function, and eventually lead to cancers. P53 is a well-known tumour suppressor gene whose mutations were commonly found in cancers.

Somatic mutations may happen randomly during the complex cell division process. DNA repair genes, such as ATM, BRCA1, BRCA2, MSH2, and MSH6, are responsible for repairing mismatches in DNA. When a DNA repair gene is mutated, somatic mutation may accumulate at a higher rate over time.

It usually takes several mutations to develop cancers. Understanding the genetics of cancer may help understand the diagnosis, treatment, and prevention of the disease.

Somatic Mutations and Germline Mutations

Somatic Mutation and Germline Mutation
Everyone inherits one copy of the gene pair from the mother and another one from the father. When a genetic mutation is present in the germ cells (which means eggs or sperm from parents) and inherited to the individuals from birth, it is referred to as germline mutation. Not all germline mutation carriers will develop cancer. However, carrying a germline mutation in a oncogene, tumor suppressor or DNA repair genes may increase the likelihood of developing cancer in a lifetime.
A somatic mutation, or acquired mutation, happens in somatic cells instead of germ cells and will not pass to offspring. A somatic mutation is frequently caused by environmental factors, such as smoking or exposure to carcinogens.