The Angora goat populations in Argentina (AR), France (FR) and South Africa (SA) have been kept geographically and genetically distinct. Due to country-specific selection and breeding strategies, there is a need to characterize the populations on a genetic level. In this study we analysed genetic variability of Angora goats from three distinct geographical regions using the standardized 50k Goat SNP Chip. A total of 104 goats (AR: 30; FR: 26; SA: 48) were genotyped. Heterozygosity values as well as inbreeding coefficients across all autosomes per population were calculated. Diversity, as measured by expected heterozygosity (HE) ranged from 0.371 in the SA population to 0.397 in the AR population. The SA goats were the only population with a positive average inbreeding coefficient value of 0.009. After merging the three datasets, standard QC and LD-pruning, 15 105 SNPs remained for further analyses. Principal component and clustering analyses were used to visualize individual relationships within and between populations. All SA Angora goats were separated from the others and formed a well-defined, unique cluster, while outliers were identified in the FR and AR breeds. Apparent admixture between the AR and FR populations was observed, while both these populations showed signs of having some common ancestry with the SA goats. LD averaged over adjacent loci within the three populations per chromosome were calculated. The highest LD values estimated across populations were observed in the shorter intervals across populations. The Ne for the Angora breed was estimated to be 149 animals ten generations ago indicating a declining trend. Results confirmed that geographic isolation and different selection strategies caused genetic distinctiveness between the populations.

Goats (Capra aegagrus hircus) have not been a prioritized livestock species with regards to molecular research. The genetic characterization of commercial South African (SA) goat breeds should contribute to improving the management of available animal genetic resources. The aim of this study was to investigate genetic diversity within and among SA commercial goat breeds utilizing the 50k goat beadchip. 88 goats originating from four breeds (dairy: British Alpine, Saanen, Toggenburg; fibre: Angora) were genotyped with the goat SNP50 beadchip. Average MAF values ranged from 0.25 for the Angora to 0.29 for the Saanen, with 46 983 and 50 368 polymorphic SNPs obtained for the respective breeds. Observed heterozygosity values ranged from 0.365 for the Angora to 0.431 for the Toggenburg breed. Linkage disequilibrium (LD) estimation revealed average r 2 values of 0.12 and 0.15 for dairy and fibre breeds, respectively. LD decay was shown to occur after a distance interval of 20-40kb and 40-60kb for dairy and Angora breeds, respectively. Principal component analysis (PCA) produced clusters corresponding to the different production types (dairy and fibre). The Angora, British Alpine and Saanen breeds showed high proportions of membership to respective inferred ancestral populations with ADMIXTURE (97%, 84% and 92%, respectively). The results obtained in this study indicated genetic uniformity within dairy and fibre goats due to productionspecific trait selection. Sufficient levels of genetic variation was, however, observed to allow genetic progress for SA commercial goat breeds pending the improved management of these goat genetic resources.

Tools for the genomic evaluation of goats have generally lagged behind those for other species. However, the recent availability of the goat SNP50 consortium bead chip has marked a positive change for this small ruminant species. Polymorphic loci can differ greatly between breeds of the same species. Exclusion of fibre-producing breeds, such as the Angora goat, during the development of this genotyping array necessitates the validation of SNPs included on the chip to allow for genomic applications that would accelerate genetic progress in mohair yield and quality. Forty eight unrelated Angora goats, displaying phenotypic variation in two important price-determining traits, namely fibre diameter and fleece weight, were genotyped with the goat SNP50 consortium bead chip. Results revealed that 46 983 SNP (88.1%) of the 53 347 called SNPs were polymorphic (MAF>0.05). After quality control, 3 960 SNP were filtered from further analysis for violating Hardy-Weinberg and call-rate parameter thresholds, leaving 43 759 (82%) of the 53 347 SNPs to be validated for downstream analysis. Observed and expected heterozygosity values of 0.365 and 0.370, respectively, were obtained for polymorphic SNPs. A total of 30 357 SNPs in linkage disequilibrium (LD) were removed to obtain a set of independent markers, resulting in a final SNP density of 1 SNP/ ~226 kb. Results indicate that the goat SNP50 bead chip was informative in the Angora goats that were studied, and should be useful in examining the underlying genetic variation. ______________________________________________________________________________________

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