Question

Define epigenome. How does the epigenome differ from the gene variants that make up the genome of an embryo?

Short answer

The 'epigenome' consists of compounds that instruct the cell genome on how to function. The 'genome' of an embryo comprises an organism’s hereditary information. The 'genome' is the raw, unchanged genetic material inherited, while the 'epigenome' dynamically modulates the genome's operation, leading to cell differentiation.

Step-by-step solution

Define the epigenome

The epigenome defines a series of chemical compounds that tell the genome what to do. They are modifications to the DNA or associated proteins, other than DNA sequence changes, that carry information during cell division.

Define the genome of an embryo

The genome of an embryo refers to the entirety of an organism’s hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. It encompasses both the genes (the coding regions), the noncoding DNA, and the genetic material of the mitochondria.

Describe the difference between the epigenome and the genome

Though both epigenome and genome are crucial for the development, functioning, and reproduction of an embryo, they fundamentally differ in their roles. The genome represents the raw genetic material – DNA sequences or gene variants that are inherited from the parents, unchanged throughout life. On the other hand, the epigenome is dynamic and can be altered by environmental conditions. The epigenome instructs the genome how, where and when to act. While the genome is the same in each cell, the epigenome can differ based on the cell type and can cause cells to become different from each other, despite having the same DNA sequence.