Does DNA change during the life?

While the sequence of DNA itself, the order of the DNA bases (A, T, C, and G), remains largely unchanged throughout an individual's life, there are other ways in which DNA and gene expression can be modified. Here are some key points to consider:

Epigenetic Changes

Epigenetics involves changes that affect how genes are expressed without altering the DNA sequence itself. These changes can include DNA methylation, histone modification, and other mechanisms that influence gene activity. Epigenetic marks can change in response to environmental factors, behaviors, and aging125.

DNA Methylation

DNA methylation, which involves the addition or removal of methyl groups from DNA, is a common type of epigenetic change. This process can turn genes "on" or "off" and can be influenced by factors such as diet, exposure to toxins, and lifestyle choices. For example, smoking can lead to decreased DNA methylation at certain genes, and quitting smoking can reverse these changes12.

Environmental and Behavioral Influences

Environmental factors, including nutrition during pregnancy, exposure to toxins, and lifestyle choices like smoking, can cause epigenetic changes that may last for decades or even be passed on to subsequent generations125.

Aging

Epigenetic changes also occur naturally as part of the aging process. Studies have shown that DNA methylation levels change over time, with some individuals gaining or losing methylation as they age12.

Genetic vs. Epigenetic Changes

It is important to distinguish between genetic changes (mutations in the DNA sequence) and epigenetic changes. Genetic changes alter the DNA sequence itself and are generally irreversible, whereas epigenetic changes affect gene expression without changing the DNA sequence and can often be reversible15.

In summary, while the DNA sequence itself does not change, the way genes are expressed and regulated can change significantly throughout an individual's life due to epigenetic modifications.