What Affects DNA?
Many factors can affect DNA. These influences range from inherited genetic changes to environmental exposures and even the natural processes within the body.
- Mutations: DNA is constantly undergoing changes, a process called mutation. These changes can be small, affecting just a few nucleotides (the building blocks of DNA), or larger, involving entire segments of chromosomes. These gene-level mutations alter the instructions genes provide, as highlighted in this Nature Scitable article. Mutations can be spontaneous or caused by internal cellular processes.
- Epigenetic Changes: These alterations do not change the DNA sequence itself, but they affect how genes are expressed. Think of it as switching genes "on" or "off" without altering the underlying code. Environmental factors can significantly influence these epigenetic modifications, as noted by the CDC and research on DNA methylation (https://dx.doi.org/10.1093/eep/dvv012). Epigenetic age, for instance, can be correlated with health outcomes independent of chronological age, according to NIH research.
- Inherited Gene Mutations: Genetic changes can be passed down from parents to their children. These inherited mutations might increase a person's risk of developing certain conditions like cancer (https://www.cancer.org/cancer/types/prostate-cancer/causes-risks-prevention/what-causes.html, https://www.cancer.gov/about-cancer/causes-prevention/genetics, https://www.autismspeaks.org/what-causes-autism).
External Factors Affecting DNA
- Environmental Mutagens: Exposure to certain chemicals, UV radiation, and other environmental factors can cause DNA damage. These agents are known as mutagens. These changes can lead to mutations and contribute to diseases like cancer (https://www.cancer.gov/about-cancer/understanding/what-is-cancer, https://www.cancer.org/cancer/types/melanoma-skin-cancer/causes-risks-prevention/what-causes.html). For example, prenatal exposure to tobacco smoke can affect DNA methylation (https://pubmed.ncbi.nlm.nih.gov/19498054/).
In summary, DNA is a dynamic molecule affected by a combination of internal cellular processes and external environmental influences. Understanding these factors is crucial in various fields, including medicine and environmental science.
