RESUMO
Sheep are considered as a major contributor of global food security. Moreover, sheep preweaning growth traits as well as in vivo carcass composition traits such as ultrasonic measurements of Longissimus dorsi muscle depth (UMD) and back-fat thickness (UFD) are crucially important indicators of meat yield and hot carcass composition. Despite their relative importance for productivity and profitability of a sheep production system, detected QTL for these traits are quite scarce. Therefore, we implemented GWAS for these traits using animal mixed model-based association approach provided by GenABEL in Esme sheep. Three genome-wide and 14 individual chromosome-wide associated SNPs were discovered. As a result, ESRP1, LOC105613082, ZNF641, DUSP5, TEAD1, SMOX, PTPRT, RALYL, POM121C, PHIP, LOC101106051, ZIM3, PEG3, TRPC7, FBXL4, LOC105610397, LOC105616489 and DNAAF2 were suggested as candidates. Some of the discovered genes and involved pathways were already annotated to contribute growth and development in various species including human, mice and cattle. All in all, the results of this study are expected to strongly contribute to shed a light on the underlying molecular mechanisms behind growth and carcass composition traits, with potential implications on studies aiming faster genetic improvement, targeted low-resolution SNP panel designs and genome-editing studies.
Assuntos
Estudos de Associação Genética/veterinária , Locos de Características Quantitativas , Ovinos , Animais , Composição Corporal/genética , Carne/análise , Camundongos , Fenótipo , Polimorfismo de Nucleotídeo Único , Ovinos/genéticaRESUMO
A total of 135 unrelated sheep from nine Turkish native sheep breeds (Daglic, Kivircik, Imroz, Chios, Morkaraman, Ivesi, Hemsin, Karayaka and Akkaraman) were investigated to determinate the maternal genetic diversity using a sequence of a 531-bp segment of the mtDNA control region. Analysis of the mtDNA control region sequence revealed 63 haplotypes and 53 polymorphic sites. Haplotype diversity, nucleotide diversity and the average number of nucleotide differences were estimated to be 0.9496 ± 0.011, 0.01407 ± 0.00060 and 7.456, respectively. The sequence analysis also revealed high level of genetic diversity among the native Turkish breeds. These breeds were grouped into three major maternal haplogroups: A, B and C, with one animal belonging from the Akkaraman breed to the rare haplogroup E. Irregular shape of mismatch distribution of haplogroup C could be an indicator that haplogroup C may represent different haplogroups. Contrarily to previous studies carried out on Turkish native breeds, majority of animals grouped in haplogroup A in the present study. This result and the irregular shape of mismatch curve of haplogroup C indicate that genetic structure of Turkish native sheep breeds could be more complicated than it is thought.
Assuntos
Mitocôndrias/genética , Ovinos/genética , Animais , Sequência de Bases , DNA Mitocondrial/química , DNA Mitocondrial/genética , Feminino , Variação Genética , Haplótipos/genética , Masculino , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Nucleotídeo Único , Alinhamento de Sequência , Análise de Sequência de DNA , TurquiaRESUMO
The genetic diversity and phylogenetic relationships of 108 individual sheep from three Turkish sheep breeds (Kivircik, Gökçeada, and Sakiz) were studied using RAPD analysis. Polymorphisms within and between populations were assayed using 15 random primers, and 82 loci were amplified ranging from 250 to 2,500 bp. The percentage of polymorphic loci was found to be 80.49, 78.05, and 73.17%, for Kivircik, Gökçeada, and Sakiz sheep breeds, respectively. Total genetic diversity was 0.2265, and the average coefficient of genetic differentiation was 0.1181. Genetically, the Gökçeada breed was more closely related to the Sakiz breed than to the Kivircik breed.
Assuntos
DNA/genética , Polimorfismo Genético , Ovinos/genética , Animais , Sequência de Bases , Cruzamento , Primers do DNA/genética , Variação Genética , Genética Populacional , Filogenia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Ovinos/classificação , TurquiaRESUMO
The genetic polymorphism of the beta-lactoglobulin gene was investigated in three native Turkish sheep breeds. The study was carried out on 108 sheep (29 Kivircik, 38 Gökçeada, and 41 Sakiz) by means of PCR-RFLP methods. Two genetic variants (A and B) and three genotypes (AA, AB, and BB) of beta-lactoglobulin have been identified. The gene frequencies of beta-LG A and B were 0.7759 and 0.2241 in Kivircik, 0.7632 and 0.2368 in Gökçeada, and 0.9756 and 0.0244 in Sakiz breeds, respectively. The populations were in Hardy-Weinberg equilibrium in all samples from the three breeds.
