Immunoglobulin genes and diversity: what we have learned from domestic animals
1 State Key Laboratory of Agrobiotechnology, College of Biological Sciences; National Engineering Laboratory for Animal Breeding, China Agricultural University, Beijing, 100193, P. R. China
2 Department of Biochemistry, Jiaozuo Teachers Colleague, Jiaozuo, 454001, Henan, P. R. China
3 College of Animal Science and Technology, Henan University of Science and Technology, Henan, 471003, P. R. China
Journal of Animal Science and Biotechnology 2012, 3:18 doi:10.1186/2049-1891-3-18Published: 20 June 2012
This review focuses on the diversity of immunoglobulin (Ig) genes and Ig isotypes that are expressed in domestic animals. Four livestock species—cattle, sheep, pigs, and horses—express a full range of Ig heavy chains (IgHs), including μ, δ, γ, ϵ, and α. Two poultry species (chickens and ducks) express three IgH isotypes, μ, υ, and α, but not δ. The κ and λ light chains are both utilized in the four livestock species, but only the λ chain is expressed in poultry. V(D)J recombination, somatic hypermutation (SHM), and gene conversion (GC) are three distinct mechanisms by which immunoglobulin variable region diversity is generated. Different domestic animals may use distinct means to diversify rearranged variable regions of Ig genes.