What are Genetic Alterations?
Genetic alterations refer to changes in the DNA sequence of a cell's genome. These changes can include mutations, deletions, amplifications, and translocations. In the context of cancer, genetic alterations can disrupt normal cellular functions, leading to uncontrolled cell growth and tumor formation.
What are Oncogenes?
Oncogenes are mutated forms of normal genes called proto-oncogenes, which promote cell growth and division. When proto-oncogenes become altered, they can become permanently activated, leading to continuous cell proliferation. Examples of oncogenes include
RAS and
MYC.
What are Tumor Suppressor Genes?
Tumor suppressor genes normally function to inhibit cell growth and promote apoptosis. When these genes are inactivated by mutations, cells can grow uncontrollably. Well-known tumor suppressor genes include
TP53,
RB1, and
BRCA1.
How Do DNA Repair Genes Affect Cancer Development?
DNA repair genes are responsible for correcting DNA damage. Mutations in these genes can lead to an accumulation of genetic errors, increasing the risk of cancer. Examples of DNA repair genes are
MLH1 and
MSH2, which are involved in mismatch repair.
Point mutations: Changes in a single nucleotide base pair.
Deletions: Loss of a segment of DNA.
Amplifications: Increased copies of a gene.
Translocations: Rearrangement of DNA segments between chromosomes.
Can Genetic Testing Help in Cancer Prevention?
Genetic testing can identify individuals at high risk for certain cancers, enabling early intervention and preventive measures. For example, testing for
BRCA1 and
BRCA2 mutations can inform about the risk for breast and ovarian cancers.
Conclusion
Genetic alterations are a cornerstone in the development and progression of cancer. By understanding these changes, researchers and clinicians can improve diagnosis, treatment, and prevention strategies, ultimately enhancing patient outcomes.
