12 research outputs found
Screening for K-Casein (CSN3) Gene Variation in Carpathian Goat Breed by Isoelectric focusing (IEF) and DNA Sequencing
In goats, k-casein (CSN3) locus is highly polymorphic with up to 16 allele currently characterized. They produce 13 protein variants (CSN3) that were classified in two groups (AIEF and BIEF), according to their isoelectric point. Isoelectric focusing (IEF) of milk samples allows the detection of these two CSN3 groups, but for correct identification of CSN3 alleles DNA based genotyping methods are needed. Therefore the objective of this study was to identify the types of alleles occurring at the CSN3 locus in Carpathian goat breed by using a combined IEF and DNA sequencing approach. IEF analysis of milk samples collected from two Carpathian goat populations reared in Romania revealed two distinct CSN3 patterns. Amplification and sequencing of CSN3 cDNA obtained from these goats revealed four polymorphic sites located in the exon 4 that are responsible for amino acids substitutions, as compared with the reference sequence of A allele. By comparative analysis of IEF and cDNA sequencing data obtained from the two populations, we shown that AIEF alleles are represented by B allele, while BIEF alleles are represented by D allele. However, the variation of CSN3 locus in Carpathian goat breed could be more complex, therefore further studies are needed to characterize it
A genome-wide perspective about the diversity and demographic history of seven Spanish goat breeds
Altres ajuts: Félix Goyache is supported by Grant FICYT GRUPIN14-113. Valentin Balteanu is the recipient of a grant awarded under the frame of the European Social Fund, Human Resources Development Operational Program 2007-2013, Project No. POSDRU/159/1.5/S/132765.Background: The main goal of the current work was to infer the demographic history of seven Spanish goat breeds (Malagueña, Murciano-Granadina, Florida, Palmera, Mallorquina, Bermeya and Blanca de Rasquera) based on genomewide diversity data generated with the Illumina Goat SNP50 BeadChip (population size, N = 176). Five additional populations from Europe (Saanen and Carpathian) and Africa (Tunisian, Djallonké and Sahel) were also included in this analysis (N = 80) for comparative purposes. Results: Our results show that the genetic background of Spanish goats traces back mainly to European breeds although signs of North African admixture were detected in two Andalusian breeds (Malagueña and MurcianoGranadina). In general, observed and expected heterozygosities were quite similar across the seven Spanish goat breeds under analysis irrespective of their population size and conservation status. For the Mallorquina and Blanca de Rasquera breeds, which have suffered strong population declines during the past decades, we observed increased frequencies of large-sized (ROH), a finding that is consistent with recent inbreeding. In contrast, a substantial part of the genome of the Palmera goat breed comprised short ROH, which suggests a strong and ancient founder effect. Conclusions: Admixture with African goats, genetic drift and inbreeding have had different effects across the seven Spanish goat breeds analysed in the current work. This has generated distinct patterns of genome-wide diversity that provide new clues about the demographic history of these populations
A high throughput genotyping approach reveals distinctive autosomal genetic signatures for European and Near Eastern wild boar
The lack of a Near Eastern genetic signature in modern European porcine breeds indicates that, although domestic pigs from the Fertile Crescent entered Europe during the Neolithic, they were completely replaced by their European counterparts in a short window of time. Whilst the absence of such genetic signature has been convincingly demonstrated at the mitochondrial level, variation at the autosomal genomes of European and Near Eastern Sus scrofa has not been compared yet. Herewith, we have explored the genetic relationships among 43 wild boar from Europe (N = 21), Near East (N = 19) and Korea (N = 3), and 40 Iberian (N = 16), Canarian (N = 4) and Mangalitza (N = 20) pigs by using a high throughput SNP genotyping platform. After data filtering, 37,167 autosomal SNPs were used to perform population genetics analyses. A multidimensional scaling plot based on genome-wide identity-by-state pairwise distances inferred with PLINK showed that Near Eastern and European wild boar populations are genetically differentiated. Maximum likelihood trees built with TreeMix supported this conclusion i.e. an early population split between Near Eastern and European Sus scrofa was observed. Moreover, analysis of the data with Structure evidenced that the sampled Iberian, Canarian and Mangalitza pigs did not carry any autosomal signature compatible with a Near Eastern ancestry, a finding that agrees well with previous mitochondrial studies
A comprehensive analysis of the genetic diversity and environmental adaptability in worldwide Merino and Merino-derived sheep breeds
Background: To enhance and extend the knowledge about the global historical and phylogenetic relationships between Merino and Merino-derived breeds, 19 populations were genotyped with the OvineSNP50 BeadChip specifically for this study, while an additional 23 populations from the publicly available genotypes were retrieved. Three complementary statistical tests, Rsb (extended haplotype homozygosity between-populations), XP-EHH (cross-population extended haplotype homozygosity), and runs of homozygosity (ROH) islands were applied to identify genomic variants with potential impact on the adaptability of Merino genetic type in two contrasting climate zones. Results: The results indicate that a large part of the Merino's genetic relatedness and admixture patterns are explained by their genetic background and/or geographic origin, followed by local admixture. Multi-dimensional scaling, Neighbor-Net, Admixture, and TREEMIX analyses consistently provided evidence of the role of Australian, Rambouillet and German strains in the extensive gene introgression into the other Merino and Merino-derived breeds. The close relationship between Iberian Merinos and other South-western European breeds is consistent with the Iberian origin of the Merino genetic type, with traces from previous contributions of other Mediterranean stocks. Using Rsb and XP-EHH approaches, signatures of selection were detected spanning four genomic regions located on Ovis aries chromosomes (OAR) 1, 6 and 16, whereas two genomic regions on OAR6, that partially overlapped with the previous ones, were highlighted by ROH islands. Overall, the three approaches identified 106 candidate genes putatively under selection. Among them, genes related to immune response were identified via the gene interaction network. In addition, several candidate genes were found, such as LEKR1, LCORL, GHR, RBPJ, BMPR1B, PPARGC1A, and PRKAA1, related to morphological, growth and reproductive traits, adaptive thermogenesis, and hypoxia responses. Conclusions: To the best of our knowledge, this is the first comprehensive dataset that includes most of the Merino and Merino-derived sheep breeds raised in different regions of the world. The results provide an in-depth picture of the genetic makeup of the current Merino and Merino-derived breeds, highlighting the possible selection pressures associated with the combined effect of anthropic and environmental factors. The study underlines the importance of Merino genetic types as invaluable resources of possible adaptive diversity in the context of the occurring climate changes
Differential distribution of Y-chromosome haplotypes in Swiss and Southern European goat breeds.
The analysis of Y-chromosome variation has provided valuable clues about the paternal history of domestic animal populations. The main goal of the current work was to characterize Y-chromosome diversity in 31 goat populations from Central Eastern (Switzerland and Romania) and Southern Europe (Spain and Italy) as well as in reference populations from Africa and the Near East. Towards this end, we have genotyped seven single nucleotide polymorphisms (SNPs), mapping to the SRY, ZFY, AMELY and DDX3Y Y-linked loci, in 275 bucks from 31 populations. We have observed a low level of variability in the goat Y-chromosome, with just five haplotypes segregating in the whole set of populations. We have also found that Swiss bucks carry exclusively Y1 haplotypes (Y1A: 24%, Y1B1: 15%, Y1B2: 43% and Y1C: 18%), while in Italian and Spanish bucks Y2A is the most abundant haplotype (77%). Interestingly, in Carpathian goats from Romania the Y2A haplotype is also frequent (42%). The high Y-chromosome differentiation between Swiss and Italian/Spanish breeds might be due to the post-domestication spread of two different Near Eastern genetic stocks through the Danubian and Mediterranean corridors. Historical gene flow between Southern European and Northern African goats might have also contributed to generate such pattern of genetic differentiation
Multidimensional scaling plot based on genome-wide identity-by-state pairwise distances inferred with PLINK.
<p>This graph displays the genetic relationships between Near Eastern, Korean and European wild boar and Iberian, Canarian and Mangalitza pigs.</p
Pairwise F<sub>ST</sub>-values between Near Eastern (NEWB) and European (EUWB) wild boar and Iberian (IB) and Mangalitza pigs (MA)<sup>1</sup><sup>,</sup><sup>2</sup>.
1<p>Far Eastern wild boar and Canarian pigs were not included in this analysis because of insufficient sample size.</p>2<p>*** <i>P</i>-value<0.001.</p
Maximum likelihood trees constructed with TreeMix depicting splits and migration events (m = 1–4) between six <i>Sus scrofa</i> populations: 1, Near Eastern wild boar; 2, Mangalitza pigs, 3, Canarian pigs; 4, Iberian pigs; 5, European wild boar; 6, Korean wild boar.
<p>Edges, whose color ranges from red to yellow depending on the weight of the migration event (measured as the fraction of alleles coming from the parental population), indicate the direction of gene flow between populations. Probabilities associated with each migration event are represented by <i>P</i>-values in bold.</p
Structure-based estimation of the admixture proportions of 83 individuals belonging to ten <i>Sus scrofa</i> populations.
<p>The method of Evanno <i>et al. </i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0055891#pone.0055891-Evanno1" target="_blank">[38]</a> indicated that the most likely number of clusters was K = 4, but Admixture analysis and a plot of the log likelihood of each K-value (see Supplementary Information) pointed to K = 5 as the most likely number of clusters. WB = wild boar.</p
