Genetic variation in BoLA microsatellite loci in Portuguese cattle breeds

Abstract

Major histocompatibility complex (MHC) typing based on microsatellites can be a valuable approach to understanding the selective processes occurring at linked or physically close MHC genes and can provide important information on variability and relationships of populations. Using microsatellites within or in close proximity with bovine lymphocyte antigen (BoLA) genes, we investigated the polymorphisms in the bovine MHC, known as the BoLA, in eight Portuguese cattle breeds. Additional data from non-BoLA microsatellite loci were also used to compare the variability between these regions. Diversity was higher in BoLA than in non-BoLA microsatellites, as could be observed by the number of alleles, allelic richness and observed heterozygosity. Brava de Lide, a breed selected for aggressiveness and nobility, presented the lowest values of observed heterozygosity and allelic richness in both markers. Results from neutrality tests showed few statistically significant differences between the observed Hardy-Weinberg homozygosity (F) and the expected homozygosity (F(E)), indicating the apparent neutrality of the BoLA microsatellites within the analysed breeds. Nevertheless, we detected a trend of lower values of observed homozygosity compared with the expected one. We also detected some differences in the levels of allelic variability among the four BoLA microsatellites. Our data showed a higher number of alleles at the BoLA-DRB3 locus than at the BoLA-DRBP1 locus. These differences could be related to their physical position in the chromosome and may reflect functional requirements for diversity.

Formation of the genetic structure of cattle populations by single locus DNA fragments depending on their productivity direction and origin

“…For zebu (Bos indicus), these were loci TGLA122 and TGLA227 (Vohra V et al, 2017), also noted in our research. The neutrality of all the investigated microsatellite loci was also noted in the studies of such local populations as Arunachali in India (Sharma H et al, 2018), and 12 local (aboriginal) breeds in Portugal (Bastos-Silveira C et al, 2009), as well as Creole local breed La Angelica (Giovambattista G et al, 2001).…”

Polymorphisms of Bovine Lymphocyte Antigen (BoLA DRB 3.2 Locus PstI) Gene in Bali Cattle Population from South Sulawesi Province

“…Class I molecules consist of an alpha chain with a molecular mass of about 45 KDa (heavy chain) associated noncovalently with β2microglobulin chain which is around 12 Kda and the molecules are expressed in all nucleated cells, and their main function is to present peptides to CD8+ T-lymphocytes, which kill virus-infected and neoplastic cells. The class II gene are distributed in two regions, II a and II b, with an approximate recombination frequency of 17% (Davies et al 1997;Bastos-Silveira et al 2008).…”

Investigação de Polimorfismos nos Genes IGF2 e CYP21 em Bovinos de Raças Zebuínas e Análise das Possíveis Associações com Características de Interesse Econômico

“…A influência dos polimorfismos genéticos nos aspectos de interesse econômico em diversas espécies de animais domésticos tem sido amplamente estudada por diferentes grupos de pesquisadores pelo mundo (Angiolillo et al, 2007;Daetwyler et al, 2008;Grisolia et al, 2009(a,b); Pang et al, 2010 No início, a procura por polimorfismos funcionais estava direcionada para a região codificadora de genes responsáveis por importantes características fenotípicas (Bastos-Silveira et al, 2009;Grisolia et al, 2009a;MacLeod et al, 2010;Rincón et al, 2009). Vários SNPs vêm sendo investigados na genética animal, em especial nos bovinos (Garrick e Golden, 2009;Yamada et al, 2009;Huang et al, 2010;Pang et al, 2010;Pryce et al, 2010;Verschoor et al, 2010;Watanabe et al, 2010;Weigel et al, 2010;) e menor proporção em raças zebus (Andrea, 2007; .…”