What are Genetic Changes in Cancer?
Cancer is fundamentally a disease of the genes. Genetic changes, also known as mutations, play a crucial role in the development and progression of cancer. These alterations can occur in several different ways, including mutations in
DNA, changes in the number or structure of chromosomes, or epigenetic changes that affect gene expression.
Types of Genetic Changes
There are several types of genetic changes that can lead to cancer: Point Mutations: A single nucleotide base is changed, inserted, or deleted from a sequence of DNA.
Chromosomal Aberrations: Large segments of DNA are duplicated, deleted, or rearranged.
Gene Amplifications: Copies of a gene are increased, leading to overexpression.
Epigenetic Changes: Modifications that affect gene activity without altering the DNA sequence, such as DNA methylation and histone modification.
How Do These Changes Lead to Cancer?
Genetic changes can activate
oncogenes or deactivate
tumor suppressor genes. Oncogenes are genes that, when mutated, become permanently activated and promote cell growth and division. Tumor suppressor genes, on the other hand, normally function to inhibit cell division and promote apoptosis. When these are inactivated, cells can grow uncontrollably.
Are Genetic Changes Inherited?
Some genetic changes can be inherited from a parent. These inherited mutations are present in every cell of the body and can increase the risk of developing cancer. However, most cancer-related genetic changes are acquired, meaning they occur during a person’s lifetime due to environmental factors such as exposure to
carcinogens, lifestyle choices like smoking, or random errors in DNA replication.
What is the Role of Genetic Testing?
Genetic testing can identify mutations that may increase an individual's risk of developing certain types of cancer. For example, mutations in the
BRCA1 and BRCA2 genes are known to significantly increase the risk of breast and ovarian cancers. Identifying these mutations can help in taking preventive measures or opting for early interventions.
Conclusion
Understanding genetic changes in cancer is crucial for the development of personalized treatment strategies. While inherited mutations contribute to a small percentage of cancers, the majority are due to acquired genetic changes. Advances in genetic testing and targeted therapies offer promising avenues for more effective and personalized cancer treatment.
