Role of epigenetic modifications in improving the thermo-tolerance, growth and immuno-competence in poultry: current status and future applications

Abstract

Epigenetics refer to the changes in gene expression that occur without any underlying change(s) in DNA sequence and can be transmitted through mitosis and/or meiosis across generations. These changes include the DNA methylation; a covalent modification of cytosine at CpGdinucleotides; role of small RNAs and chromatin modifications including histone acetylation, methylation, phosphorylation and others. Though a relatively naive concept in biological sciences, epigenetics has been more researched upon in mammalian species and there is scarcity of studies on poultry species. Epigenetics can also be thought of as those processes that regulate the gene expression in a given cell leading to a particular cellular phenotype. Nutrients, bioactive compounds, environmental factors and hormones trigger changes in the environment of the cell and affect epigenetic phenotype. Nutrigenomics and nutrigenetics are part of the epigenetic studies and are highly correlated to each other. Imprinting and silencing of genes are helpful in deciphering the secrets of natural diversity in different poultry species and variations in their performance and other attributes. By manipulating at gene regulation and expression steps, epigenetic mechanisms play important roles in improving production, immunocompetence, stress regulation as well as health and welfare of poultry. The present review is aimed at highlighting the current status and future applications of epigenetics for improving production, disease resistance and other attributes in poultry.