Characterization of bovine MHC DRB3 diversity in worldwide cattle breeds focusing on Myanmar cattle

PALATI M.; TAKESHIMA S-N; MOE K.K.; MOE H.H.; GIOVAMBATTISTA G.; BORJIGIN L. ; AIDA Y.

LLeida

Conferencia; 37th International Society for Animal Genetics Conference; 2019

International Society for Animal Genetics

Myanmar cattle population is mainly comprised by native breeds and Holstein crossbreeds, which are composed of bovines highly adapted to the harsh tropical climates of this country. Myanmar native cattle included different breeds that are defined by their geographical location and coat color. The main aim of this work was to assess the genetic diversity and genetic structure of the BoLa-DRB3 gene in the Myanmar cattle population at allele and molecular levels, a locus that play a role in the immune response and resistence to infectious diseases. Blood samples were obtained from 294 cattle from 6 regions of Myanmar (Bago, n = 38; Sagaing, n = 77; Mandalay, n = 46; Magway, n = 46; Kayin, n = 43; and Yangon, n = 44). Purified DNAs were genotyping by the SBT method and DNA electropherograms were analyzed using Assign 400ATF software. 71 alleles were detected in Myanmar cattle, including 4 new variants. AMOVA evidenced that intra- and inter-breed genetic diversity in the BoLA-DRB3 gene of Holstein and Native groups and inter-groups account for the 0.4% and 2%, respectively of the genetic variances at BoLA-DRB3 gene, respectively, (FST range between 0 - 0.054). The gene diversity within population varied between 0.976 in Kayin Native and 0.916 in Kayin Holstein, respectively, while, the number of alleles ranged from 12 in Bago Holstein to 40 in Sagaing native. PCA and tree analyzes showed that Myanmar native populations grouped in a narrow cluster that diverges clearly from the Myanmar crossbreed Holstein crossbred populations. Furthermore, some Myanmar native populations (Bago, Mandalay and Yangon) seem to be closer to Zebu breeds (Nellore, Gir, and Brahman), while others (Kayin, Magway and Sagaing) are more related to Philippine native in that BoLA-DRB3 gene. On the contrary, the Holstein population showed a large dispersion, probably due to the different degree of mixing with native populations. The results presented in the current work will contribute to increase our knowledge about the genetic diversity of BoLa-DRB3, and how this diversity is distributed among Myanmar regions.