Epigenetics, the study of the chemical modification of specific genes or gene-associated proteins of an organism. Epigenetics studies have revealed that chemical modifications to histones can be inherited and define how the information in genes is expressed and used by cells.

Some people are genetically predisposed to higher stress levels. While all of us feel stressed at some point or another, some people battle with stress more frequently. This boils down to genetics. Your genes produce proteins which dictate how your body functions.

Disease may be caused by direct changes in epigenetic marks, such as DNA methylation, commonly found to affect imprinted gene regulation. Also described are disease-causing genetic mutations in epigenetic modifiers that either affect chromatin in trans or have a cis effect in altering chromatin configuration.

Mothers can influence epigenetic marks on their offspring’s DNA as well, changing how their baby will react to stress, whether or not they grow up healthy, and their ability to learn, remember and adapt as adults. The Mediterranean diet during pregnancy was shown to epigenetically reduce a child’s risk of disease.

Can epigenetic changes be permanent? Possibly, but it’s important to remember that epigenetics isn’t evolution. It doesn’t change DNA. Epigenetic changes represent a biological response to an environmental stressor.

The new findings show that inherited epigenetic marks affect gene expression and development. But the study involved artificially changing the marks on the sperm chromosomes. If it changes gene expression patterns in the germline, we expect that those changes can be inherited, but we haven’t shown that yet.”

DNA methylatoin patterns are passed on to progeny cells by the actio of an enzyme that copies the methylation pattern on the parent DNA strand of an enzyme that copies the methyaltion pattern on the parent DNA strand to the daughter DNA strand immediately after replication figure 8-22.

Scientists use maps of the chromosomes (similar to a road map) to look for genes. Searching for genes that cause a specific disorder is somewhat like trying to find a street on a map of the world. Using certain landmarks the location can be narrowed down.

DNA methylation regulates gene expression by recruiting proteins involved in gene repression or by inhibiting the binding of transcription factor(s) to DNA. As a consequence, differentiated cells develop a stable and unique DNA methylation pattern that regulates tissue-specific gene transcription.