Question

What is epigenetics?

Answer 1

Epigenetics refers to heritable changes in our gene expression that do not alter our DNA .

Explanation:

This means that our phenotype , what is expressed, is altered in some way without altering our DNA due to external or environmental variables. Genes may be expressed or silenced or read differently, but the underlying DNA code remains the same.

These epigenetic changes can happen due to DNA methylation, histone modification, and RNA-associated silencing.

DNA methylation adds a methyl group to the DNA, which changes transcription. Histone modification works by adding either an acetyl or methyl group to lysine located in the histone. Non-coding RNAs, antisense RNA, and RNA interference may also alter expression by causing histone modification, methylation, and by causing heterochromatin to form. All of these examples mentioned in the previous sentence silence genes.

Epigenetic changes may be beneficial, harmful, or completely neutral. Recent epigenetic work has suggested that trauma may be inherited , the epigenetics of a father's sperm affects his offspring's risk of autism, and mothers consuming a diet high in fiber may reduce their child's risk of asthma .

Here's a good site from the University of Utah and Nature also has an excellent webpage on this topic.