Optimization of Total DNA Extraction from Dried Blood Samples.

While dried blood spots are a convenient source of genetic material, they are usually associated with a lower DNA yield than from a native sample. The study evaluated the DNA yield from dried blood samples prepared on glass fibre and cellulose membranes and investigated the reasons for the yield reduction. The extraction of total DNA from membrane-dried blood samples was optimized by spin-column extraction method. It was shown that preliminary short-term (20 min) solubilization of a dried matrix in an aqueous medium, followed by standard extraction protocols for the mixture of the eluate with membranes, provides the highest DNA yield. The yield of DNA from a glass fibre membrane was 40-50% lower compared to a native sample, but on average, two times higher than from a conventional cellulose membrane (filter paper). The reduction of DNA yield when using a dried sample was found to be due to partial retention of nucleic acids by the membrane material during the lysis stage.

Genetic Diversity, Population Structure and Phylogeny of Indigenous Goats of Mongolia Revealed by SNP Genotyping.

Mongolian goats are of great interest for studying ancient migration routes and domestication, and also represent a good model of adaptability to harsh environments. Recent climatic disasters and uncontrolled massive breeding endangered the valuable genetic resources of Mongolian goats and raised the question of their conservation status. Meanwhile, Mongolian goats have never been studied on genomic scale. We used Illumina Goat SNP50 to estimate genetic risks in five Mongolian goat breeds (Buural, Ulgii Red, Gobi GS, Erchim, Dorgon) and explored phylogenic relationships among these populations and in the context of other breeds. Various clustering methods showed that Mongolian goats grouped with other Asian breeds and were especially close to some neighboring Russian and Chinese breeds. The Buural breed showed the lowest estimates of inbreeding and exhibited the shortest genetic distances within the other Mongolian breeds, especially, to Ulgii Red and Gobi GS. These three breeds formed a single core group, being weakly differentiated from each other. Among them, Gobi GS displayed obvious signs of inbreeding probably resulted from artificial selection pressure. Dorgon and especially Erchim goats stand apart from the other Mongolian breeds according to various types of analyses, and bear unique features pointing to different breeding histories or distinct origins of these breeds. All populations showed strong decline in effective population size. However, none of them met formal criteria to be considered as endangered breeds. The SNP data obtained in this study improved the knowledge of Mongolian goat breeds and could be used in future management decisions in order to preserve their genetic diversity.

The genetic origin and history of speed in the Thoroughbred racehorse.

Selective breeding for speed in the racehorse has resulted in an unusually high frequency of the C-variant (g.66493737C/T) at the myostatin gene (MSTN) in cohorts of the Thoroughbred horse population that are best suited to sprint racing. Here we show using a combination of molecular- and pedigree-based approaches in 593 horses from 22 Eurasian and North-American horse populations, museum specimens from 12 historically important Thoroughbred stallions (b.1764-1930), 330 elite-performing modern Thoroughbreds and 42 samples from three other equid species that the T-allele was ancestral and there was a single introduction of the C-allele at the foundation stages of the Thoroughbred from a British-native mare. Furthermore, we show that although the C-allele was rare among the celebrated racehorses of the 18th and 19th centuries, it has proliferated recently in the population via the stallion Nearctic (b.1954), the sire of the most influential stallion of modern time, Northern Dancer (b.1961).