Journal of Animal Breeding and Genomics (J Anim Breed Genom)
Indexed in KCI
OPEN ACCESS, PEER REVIEWED
pISSN 1226-5543
eISSN 2586-4297
Review Article

Adaptive evolution of β-defensin gene clusters by gene duplication and loss during environmental changes in mammals

Department of Stem Cell and Regenerative Biotechnology, Konkuk University, Seoul 05029, Korea

Correspondence to Chankyu Park, E-mail: chankyu@konkuk.ac.kr

Volume 6, Number 4, Pages 143-154, December 2022.
Journal of Animal Breeding and Genomics 2022, 6(4), 143-154. https://doi.org/10.12972/jabng.20220016
Received on September 02, 2022, Revised on November 09, 2022, Accepted on December 05, 2021, Published on December 31, 2022.
Copyright © 2022 Korean Society of Animal Breeding and Genetics.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0).

ABSTRACT

Recent progress in genome projects for diverse species allows understanding of specific differences in genetic information among diverse species. Antimicrobial peptides (AMPs) are found in various species including plants, insects, and vertebrates and serve as a first line defense system that exhibits a broad and antimicrobial reactions against pathogens. Several families of classical AMPs have been identified, including defensins, cathelicidins, dermcidin, hepcidin, NK-lysin and granulysin. Interestingly, the number of AMP family genes among mammalian species varies and this could be attributed to differences in the opportunistic exposure to pathogens according to their living environments or habitats. In this review, we discussed the current finding on differences in the copy number of AMP genes in mammals and possible mechanisms associated to copy number difference especially in β-defensins, one of major AMP families. This review suggest that environmental changes could contribute to the evolution of the innate immune system in mammals.

KEYWORDS

genome duplication, copy number variation, antimicrobial peptides, mammalian evolution, and environmental change

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