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Description of Genetics

Description of Genetics

What is genetics?

Genetics is the branch of medicine concerned with how hereditary and genetic factors play a role in causing a disease, birth defect, or inherited susceptibility to a health problem, such as cancer.

Cancers develop due to alterations (mutations) in genes, that when working properly, promote normal, controlled cell growth. Only a small percentage of cancers involve inherited mutations that are passed from generation to generation. The majority of cancers can be attributed to acquired mutations. "Acquired" means that the mutations occur at the cellular level after birth, as a result of environmental exposures (such as radiation), lifestyle behaviors (such as smoking, eating poorly, or not exercising), or chance alone. Acquired changes occur only in the tissue that is affected by cancer (for example, colon cancer cells). Acquired changes are not passed to children. Mutations in a person's DNA accumulate over time. If mutations affect genes that control cell growth, this may cause a cell to grow out of control and, ultimately, become a cancer cell.
