FST Genetic Distances Research Articles

Genetic Diversity Losses in Mantis Shrimp Oratosquilla oratoria Offspring Created for Supportive Releases Using an Ecological Breeding in Earthen Pond Method

ABSTRACTArtificial breeding of mantis shrimp Oratosquilla oratoria, using the ecological breeding in earthen pond (EBEP) method, has been carrying out from 2019, and the produced larvae have always been used for supportive breeding programs in Bohai Bay. To assess the degree of fidelity of enhancement programs used an EBEP method to native genetic pools, genetic diversity at 10 microsatellite loci was analyzed in three hatchery offspring populations, their wild parent stocks, and their wild contemporaneous offspring. Significant decrease in the almost genetic diversity parameters and highly significant differences in shannon's information index (decreasing by 22.54%–40.97%) and allelic richness (33.80%–46.87%) were observed between in hatchery populations. This further created relatively more genetic differentiation between the hatchery and wild population, as the pairwise Fst values and genetic distances showed. The mean pairwise relatedness coefficients showed higher values within hatchery populations and lower values within wild populations. Hatchery populations contained the fewest full‐sib families and offspring were extremely distributed in 10–11 full‐sib groups in each hatchery population. The relatively small number of actual spawning females and large variance in parental contribution to the next generation possibly causes allele reduction in the hatchery population, which in turn leads to a decrease in allelic diversity and an increase in genetic similarities among individuals. Promoting synchrony of ovarian development in females, providing good conditions for incubation and larvae culture and balancing the contributions of parents will be important in future breeding propagation.

Molecular Genotyping Analysis Suggested High Clonality and Simple Marker Loci in Puccinia striiformis f. sp. tritici Population in Uzbekistan, Central Asian Region.

Puccinia striiformis f. sp. tritici (Pst) is a destructive pathogen that causes wheat stripe rust worldwide. Understanding the population structure and dynamic of pathogen spread is critical to fight against this disease. Limited information is available for the population genetic structure of Pst in Uzbekistan, Central Asia. In this study, we carried out surveillance from nine different regions (Andijan, Fergana, Jizzakh, Kashkadarya, Namangan, Samarkand, Sirdaryo, Surkhandarya, and Tashkent) of Uzbekistan to fill this gap. A total of 255 isolates were collected, which were genotyped using 17 polymorphic simple sequence repeat markers. The DAPC analysis results showed no population subdivision in these sample-collected regions except Surkhandarya. Multilocus genotype (MLG) analysis, FST, and Nei's genetic distance results indicated a clonal population (rBarD ≤ 0.12) and merely three MLGs accounting for 70% of the overall population. MLG-34 was predominant in all regions of Uzbekistan, followed by MLG-36 and MLG-42. Low genotypic diversity was observed in Andijan, Fergana, Jizzakh, Kashkadarya, Namangan, Sirdaryo, and Tashkent (0.56 to 0.76), compared with Samarkand (0.82) and Surkhandarya (0.97). No virulence against Yr5, Yr15, YrSp, and Yr26 was found, while resistance was overcome against Yr1, Yr2, Yr6, Yr9, Yr17, and Yr44 genes (virulence frequency ≥75%). Comparative study results of Uzbekistan with the previous Himalayan population showed divergence from China and Pakistan populations. Further studies need to be conducted in a worldwide context to understand migration patterns; for that purpose, collaborative work is essential because of the Pst long-distance migration capability.

Analysis of maternal genetic structure of mitochondrial DNA control region from Tai-Kadai-speaking Buyei population in southwestern China

BackgroundEven though the Buyei are a recognised ethnic group in southwestern China, there hasn’t been much work done on forensic population genetics, notably using mitochondrial DNA. The sequences and haplogroups of mitochondrial DNA control regions of the Buyei peoples were studied to provide support for the establishment of a reference database for forensic DNA analysis in East Asia.Methods and resultsThe mitochondrial DNA control region sequences of 200 Buyei individuals in Guizhou were investigated. The haplotype frequencies and haplogroup distribution of the Buyei nationality in Guizhou were calculated. At the same time, the paired Fst values of the study population and other populations around the world were computed, to explore their genetic polymorphism and population relationship. A total of 179 haplotypes were detected in the Buyei population, with frequencies of 0.005–0.015. All haplotypes were assigned to 89 different haplogroups. The haplotype diversity and random matching probability were 0.999283 and 0.0063, respectively. The paired Fst genetic distances and correlation p-values among the 54 populations revealed that the Guizhou Buyei was most closely related to the Henan Han and the Guizhou Miao, and closer to the Hazara population in Pakistan and the Chiang Mai population.ConclusionsThe study of mitochondrial DNA based on the maternal genetic structure of the Buyei nationality in Guizhou will benefit the establishment of an East Asian forensic DNA reference database and provide a reference for anthropological research in the future.

Genome-Wide Insights into Intraspecific Taxonomy and Genetic Diversity of Argali (Ovis ammon)

Argali (Ovis ammon), the largest species among all wild sheep, is native to mountainous regions of Central and East Asia, spreading mainly throughout such countries as Tajikistan, Kyrgyzstan, Kazakhstan, Afghanistan, Mongolia, Russia and China. Intraspecific taxonomy of argali remains unclear, and currently, most researchers recognize up to nine subspecies. The aim of our work was to investigate the phylogenetic relationship between populations of O. ammon based on genome-wide SNP analysis. Five subspecies, Altai (O. a. ammon) (n = 6), Gobi (O. a. darwini) (n = 5), Pamir (O. a. polii) (n = 12), Tian Shan (O.a. karelini) (n = 15) and Kyzylkum (O. a. severtzovi) (n = 4), were genotyped using Illumina OvineHD BeadChip. In addition, complete mitogenome sequences from 30 of those samples were obtained. After quality control procedures, 65,158 SNPs were selected for the subsequent analyses. Neighbor-Net dendrogram and principal component analysis (PCA) revealed that the five subspecies could be grouped into four clusters. It was shown that a population from Altai formed a cluster with Gobi subspecies. The highest pairwise FST genetic distance was between O. a. ammon and O. a. severtzovi (0.421) and the lowest were between O. a. polii and O.a. karelini (0.083) and between O. a. ammon and O. a. darwini (0.040) subspecies. Genetic diversity was higher in Central Asian argali as compared to East Asian populations. O. a. severtzovi had an admixed origin and consisted of two genetic components—73.5 ± 0.2% of O. a. polli and 26.5 ± 0.2% of urial (O. vignei). TreeMix analysis revealed a migration event from urial to O. a. severtzovi argali. The analysis of complete mitogenomes supported the results based on whole-genome genotyping. Considering that all the mtDNA sequences of O. a severtzovi belonged to O. ammon and not to O. vignei, we concluded that gene flow in this group was associated with urial males. As this is only the first work on intraspecific taxonomy and genetic diversity of argali based on genome-wide SNP genotyping and the analysis of complete mitogenomes, we suggest that more genetic studies are needed to clarify the status of Gobi and Tian Shan argali.

Genetic features and phylogenetic relationship analyses of Guizhou Han population residing in Southwest China via 38 X-InDels.

The insertion/deletion polymorphism (InDel), an ideal forensic genetic marker with a low spontaneous mutation rate and small amplification product fragments, is widely distributed in the genome, combining the advantages of STR and SNP genetic markers. The X-chromosome has high application value in complex paternity testing, and it is an excellent system for evaluating population admixture and studying evolutionary anthropology. However, further research is needed on the population genetics of X-chromosome InDels (X-InDels). In this article, a system composed of 38 X-InDel loci was utilized to analyse and evaluate the forensic parameters of the Guizhou Han population in order to explore its forensic application efficiency. The results showed that expected heterozygosities spanned from 0.0189 to 0.5715, and the cumulative power of discrimination of the 32 X-InDels and three linkage blocks was 0.9999999954 and 0.999999999999741 for males and females, respectively. The combined mean exclusion chance of these loci for trios and duos is 0.999999 and 0.999747, respectively. Multiple methods like principal component analysis, Fst genetic distance, and phylogenetic reconstruction were employed for dissecting the genetic structure of the Guizhou Han population by comparing it with previously reported populations. As expected, the studied Han population displayed relatively close genetic affinities with the East Asian populations. At the same time, there were obvious genetic differentiations between the Guizhou Han population and other continental populations that were discerned, especially for the African populations. This study further verified the applicability of 38 X-InDels for human personal identification and kinship analyses of Han Chinese, and also showed the application potential of X-InDels in population genetics.

Postglacial Expansion Routes and Mitochondrial Genetic Diversification of the Freshwater Pearl Mussel in Europe and North America

The freshwater pearl mussel Margaritifera margaritifera is a unionid species distributed across Northwestern Russia, Fennoscandia, Western and Southwestern Europe, and the Atlantic Coast of North America. In this study, we reconstructed the post-glacial expansion routes of this species based on FST genetic distances and the fact that M. margaritifera distribution is directly connected with salmonid expansion. The freshwater-pearl-mussel populations from North America and Northeastern Europe were the closest groups, judging by FST distances, supporting the concept of the North Atlantic Salmo salar colonization of the Barents and White Sea basins. We also documented that unique haplotypes in the populations of the Baltic and White Sea basins may have originated in isolated glacial refugia in Eastern and Northeastern Europe. The Iberian clade was the most distant group of populations, which is consistent with the previously observed role of the Iberian Peninsula as a glacial refugium. The high genetic diversity in the populations of Northern and Eastern Karelia was facilitated by migrants utilizing complex periglacial hydrological networks and by admixture in the contact zone where the migration flows met. We confirm that this region should be considered as a major center of genetic diversity within the European part of the species’ range.

Investigation of X-STR haplotype diversity in the Australian Aboriginal population

ABSTRACT X-chromosome short tandem repeat (X-STR) analysis complements autosomal and Y-chromosome STR typing for complex kinship analysis and screening of candidate lists in familial searches. To statistically evaluate X-STR profiling results, Australian forensic laboratories require X-STR haplotype frequency databases for relevant populations. Our study is the first to report haplotype data for the Australian Aboriginal population. X-STR haplotypes were generated for 298 self-declared male Aboriginals using the Investigator® Argus X-12 Kit. Haplotype frequencies and parameters of forensic interest are presented. The discrimination power of a full haplotype was 98.7% and the cumulative power of discrimination was 0.9999999988 for males and 0.999999999999999 for females. MDS plots of pairwise FST genetic distances and STRUCTURE histograms identified some segregation of X-STR haplotypes between individuals from the Desert and Eyre regions as compared to the Spencer, Riverine and urban Adelaide regions. Comparison of Australian Aboriginal X-STR haplotypes to those of other global populations showed the most similarity to Europeans and least similarity with Asian populations. Ancestral X-STR haplotypes appeared most conserved in the outback Desert and Eyre regions where assimilation with Europeans is lower. Overall genetic structure was minimal and a single X-STR haplotype database combining all regions is considered appropriate for likelihood ratio calculation.

Population Structure, Genetic Diversity and Differentiation of Triplophysa tenuis in Xinjiang Tarim River.

Triplophysa tenuis is an important indigenous fish in the Xinjiang Tarim River. In this study, we collected 120 T. tenuis individuals from 8 T. tenuis populations in the Tarim River. Through genotyping-by-sequencing (GBS), a total of 582,678,756 clean reads were generated for all the genotypes, and after quality filtering, 595,379 SNPs were obtained for the population genetic analyses. Multiple genetic parameters showed that the 8 T. tenuis populations had high genetic diversity. Phylogenetic tree analysis indicated that all T. tenuis individuals were divided into five branches, the individuals from the north of Tarim River were grouped into cluster 1 (SF and WS) and cluster 3 (DWQ, TKX, and KZE), while the AETS, WLWT and LF individuals from the south of Tarim River were clustered into cluster 2. The result was consistent with the admixture analysis, which supported that the 8 T. tenuis populations were clustered into three subgroups. Furthermore, the pairwise F ST values and genetic distance indicated that there was a large genetic differentiation between WS and other T. tenuis populations. Collectively, this study provides valuable genome-wide data for the conservation of natural T. tenuis populations in the Tarim River.

The Genetic Structure and East-West Population Admixture in Northwest China Inferred From Genome-Wide Array Genotyping.

Northwest China is a contacting region for East and West Eurasia and an important center for investigating the migration and admixture history of human populations. However, the comprehensive genetic structure and admixture history of the Altaic speaking populations and Hui group in Northwest China were still not fully characterized due to insufficient sampling and the lack of genome-wide data. Thus, We genotyped genome-wide SNPs for 140 individuals from five Chinese Mongolic, Turkic speaking groups including Dongxiang, Bonan, Yugur, and Salar, as well as the Hui group. Analysis based on allele-sharing and haplotype-sharing were used to elucidate the population history of Northwest Chinese populations, including PCA, ADMIXTURE, pairwise Fst genetic distance, f-statistics, qpWave/qpAdm and ALDER, fineSTRUCTURE and GLOBETROTTER. We observed Dongxiang, Bonan, Yugur, Salar, and Hui people were admixed populations deriving ancestry from both East and West Eurasians, with the proportions of West Eurasian related contributions ranging from 9 to 15%. The genetic admixture was probably driven by male-biased migration- showing a higher frequency of West Eurasian related Y chromosomal lineages than that of mtDNA detected in Northwest China. ALDER-based admixture and haplotype-based GLOBETROTTER showed this observed West Eurasian admixture signal was introduced into East Eurasia approximately 700 ∼1,000 years ago. Generally, our findings provided supporting evidence that the flourish transcontinental communication between East and West Eurasia played a vital role in the genetic formation of northwest Chinese populations.

Genetic variability of dairy cattle breeds in Lithuania

Large numbers of different scientific studies are conducted to preserve the breeds and improve the existing ones by introducing the variability of the plate genes, which best shows the phenotypic characteristics that can improve the health of dairy cattle and the quality of their production. The main purpose of this study was to perform an analysis of genetic variability of Lithuanian cattle breeds. Three subpopulation groups were studied: Lithuanian Black and White (95 individuals), Lithuanian Red (49), and Lithuanian White and Red (48). Bovine genetic material was genotyped using a total of 11 fluorescent microsatellite primers to estimate genetic variability. All loci presented a high degree of polymorphism and a total of 292 different alleles (Na) were detected. Thirty-two private alleles were detected in all evaluated subpopulations. After completing pairwise population assignment, which is based on the distribution of allelic frequencies, three populations showed the tendency to group into three separate clusters. However, the performed Principal Coordinates Analysis (PCoA), which is based on genetic distances, showed no anticipated clear grouping. Bayesian structure analysis revealed three genetic clusters. Analysis of FST (0.001–0.027) and Nei genetic distance (0.029–0.084) revealed that the genetic diversity of inter subpopulation in cattle groups was estimated to be lower than the genetic diversity of intra subpopulation.

Genomic Insight Into the Population Structure and Admixture History of Tai-Kadai-Speaking Sui People in Southwest China.

Sui people, which belong to the Tai-Kadai-speaking family, remain poorly characterized due to a lack of genome-wide data. To infer the fine-scale population genetic structure and putative genetic sources of the Sui people, we genotyped 498,655 genome-wide single-nucleotide polymorphisms (SNPs) using SNP arrays in 68 Sui individuals from seven indigenous populations in Guizhou province and Guangxi Zhuang Autonomous Region in Southwest China and co-analyzed with available East Asians via a series of population genetic methods including principal component analysis (PCA), ADMIXTURE, pairwise Fst genetic distance, f-statistics, qpWave, and qpAdm. Our results revealed that Guangxi and Guizhou Sui people showed a strong genetic affinity with populations from southern China and Southeast Asia, especially Tai-Kadai- and Hmong-Mien-speaking populations as well as ancient Iron Age Taiwan Hanben, Gongguan individuals supporting the hypothesis that Sui people came from southern China originally. The indigenous Tai-Kadai-related ancestry (represented by Li), Northern East Asian-related ancestry, and Hmong-Mien-related lineage contributed to the formation processes of the Sui people. We identified the genetic substructure within Sui groups: Guizhou Sui people were relatively homogeneous and possessed similar genetic profiles with neighboring Tai-Kadai-related populations, such as Maonan. While Sui people in Yizhou and Huanjiang of Guangxi might receive unique, additional gene flow from Hmong-Mien-speaking populations and Northern East Asians, respectively, after the divergence within other Sui populations. Sui people could be modeled as the admixture of ancient Yellow River Basin farmer-related ancestry (36.2–54.7%) and ancient coastal Southeast Asian-related ancestry (45.3–63.8%). We also identified the potential positive selection signals related to the disease susceptibility in Sui people via integrated haplotype score (iHS) and number of segregating sites by length (nSL) scores. These genomic findings provided new insights into the demographic history of Tai-Kadai-speaking Sui people and their interaction with neighboring populations in Southern China.

Study of 17 X-STRs in Native American and Mestizo populations of Central America for forensic and population purposes.

In the present work, an extensive analysis of the X-chromosomal pool of Native American and Mestizo groups of Central America (Guatemala, El Salvador, Nicaragua, and Panama) has been carried out. Allele and haplotype frequency databases, as well as other forensic parameters for these populations, are presented. The admixture analysis supports the tri-hybrid composition in terms of ancestry in the Mestizo populations, with a predominant Native American contribution (54-69%), followed by European (19-28%) and African contributions (12-19%). Pairwise FST genetic distances highlight the genetic proximity between the northernmost Central American populations, especially among admixed populations. The unique and complex nature of this area, where populations from different origins intercrossed, as well as the informativity of X-STR data, highpoint the great interest of this genetic study. Furthermore, the X-chromosome databases for Central American populations here provided will be not only useful for forensic and population purposes not only in the target countries but also in the host countries.

Polymorphism and Forensic Application of 11 Y-SNP in Guizhou Shui Ethnic Group

Objective To investigate the frequency distribution features of 11 Y-SNP of Guizhou Shui ethnic group, explore its genetic relationship with other ethnic groups and evaluate its forensic application value. Methods Multiplex amplification of the 11 Y-SNP of samples of 180 unrelated male individuals from Guizhou Shui ethnic group was performed with microsequencing technique. The frequency of haplogroup was calculated by direct counting method, and principal component analysis （PCA） of Guizhou Shui ethnic group and reference ethnic groups was performed by using Multi-variate statistical package （MVSP）. The Fst genetic distance between Guizhou Shui ethnic group and other ethnic groups was calculated with Arlequin v3.5. The phylogenetic tree was established with MEGA 4.0 software according to the Fst value. Results Six types of Y chromosome haplogroups were observed in total. Among which, the distribution frequency of O-M175 haplogroup was the highest （71.11%）, followed by C-M130 （25.00%）, and D-M174 （3.89%）. O1b-M268 （31.11%） and O2a2-IMS-JST021354 （28.33%） had a relatively high distribution frequency in O haplogroup. The paternal relationship between Guizhou Shui ethnic group and Guizhou Gelao ethnic group in the same language group was the closest. Conclusion The distribution of Y-SNP haplogroup of the Shui ethnic group in Guizhou has certain specificity, which can provide basic data for forensic biogeographic inference.

PSIII-13 Genetic assessment of isolated reindeer (Rangifer Tarandus) population from Tuva, Russia

Abstract Reindeer herding is traditional in Tuva, Russia. This region is located in the southern part of the country, on the border with Mongolia and isolated from the other reindeer herding areas of Russia. During the last three decades, the census population size of Tuva reindeer has decreased drastically, from 15,000 to 1,500 heads. The aim of our study was to assess genetic characteristics of Tuva population of reindeer. Samples of Tuva reindeer (n = 12) were genotyped using Illumina BovineHD BeadChip. To perform the comparison with other ecotypes of domestic reindeer we added samples of all the breeds, which are officially recognized in Russia: the Chukotka (n = 12), the Nenets (n = 31), the Even (n = 12) and the Evenk from Yakutia (n = 12) and Krasnoyarsk region (n = 19). Reindeer from Mongolia (n = 11) as well as the wild reindeer from Yakutian and Taimyr tundra (n = 20), and Baikal and Amur taiga (n = 9) were added to our dataset. After quality control, 7,202 SNPs were selected for subsequent analyses. On PCA plot Tuva reindeer were clustered together with Mongolian reindeer. The FST genetic distance was lowest between these two groups – 0.039 comparing to FST values between Tuva and other groups of domestic reindeer, which ranged from 0.092 (the Evenk from Yakutia) to 0.137 (the Chukotka) and were highest between Tuva and wild reindeer populations (0.146). Allelic richness was lowest in Mongolia (1.288±0.004) and Tuva reindeer (1.301±0.004). In other breeds this parameter ranged from 1.323±0.004 (the Chukotka) to 1.356±0.004 (the Evenk from Yakutia). In our study, it was shown that reindeer from Tuva do not belong to any official breed of Russia and genetically are very close to Mongolian ecotype. Our results should be considered at developing programs for restoration of Tuva reindeer. This work was supported by Russian Science Foundation grant 16-16-10068-P

Taxonomic Differentiation of Iberian Knapweeds (Centaurea sects. Jacea and Lepteranthus, Asteraceae) and Genetic Isolation of Infraspecific Floral Morphotypes

The taxonomic boundaries of Centaurea L. species and infraspecific taxa are often blurred by hybridizations. However, counterbalancing genetic isolation contributes to maintaining taxonomic limits and fostering rapid speciation processes. Radiant (R) and non-radiant (NR) capitula are two major floral morphs present in Centaurea. However, it is unclear how gene flow affects the distribution of floral morphotypes across populations and taxa. We have investigated the taxonomic differentiation and potential effect of genetic isolation in R and NR populations of Iberian Centaurea sects. Jacea (Mill.) Pers. ex Dumort. and Lepteranthus (Neck. ex DC.) Dumort. A total of 510 individuals from 58 populations (12 taxa) were analyzed using 165 amplified fragment length polymorphism (AFLP) markers. Genetic diversity and structure parameters were estimated at the taxon, population, and floral morphotypic levels. We tested whether there was correlation between population pairwise fixation index (Fst) genetic distances and the inbreeding coefficient (Fis), taken as a surrogate of reproductive isolation between the R and NR morphotypes of each group, and also taking into account geographic distances, using distance-based redundancy analysis (dbRDA). We also performed isolation by distance (IBD) tests between different floral morphotypes, aiming to infer the impact of genetic isolation on evolutionary and taxonomic divergence of the individuals. The taxa of Centaurea sects. Jacea and Lepteranthus constitute independent evolutionary lineages. Most of the detected genetic clusters match the taxonomic circumscription proposed in our most recent treatments. Genetic diversity was highest in C. debeauxii Godr. & Gren. subsp. debeauxii and subsp. grandiflora (Gaudin ex Schübl. & G. Martens) Devesa & Arnelas and in C. jacea L. subsp. angustifolia (DC.) Gremli (R) and lowest in C. nevadensis Boiss. & Reut. (NR) within the Centaurea sect. Jacea clade, whereas it was highest in C. linifolia L. within the Centaurea sect. Lepteranthus clade. Population-level dbRDA tests did not detect a significant correlation of R versus NR genetic distances and Fis values in any of the studied cases; by contrast, they detected significant correlation with longitude (C. jacea subsp. angustifolia, C. debeauxii, C. linifolia–C. stuessyi Arnelas, Devesa & E. López) or latitude (C. nigra L.). IBD analysis at the individual level showed that, in addition to geography, other morphotype-related factors may affect the genetic differentiation of R versus NR morphs in C. nigra, C. debeauxii, and C. linifolia–C. stuessyi. These results suggest that the fixation of the different morphs within the same taxon or group may be explained by geographic isolation, though we could not discount other potential unknown factors that could have contributed to microspeciation in these recently divergent populations, which originated only several thousands of years ago.

Population genetic study of a Peruvian population using human identification STRs.

In this study, allele frequencies were determined in a Peruvian population for application to human identification. A population of 601 unrelated individuals was analyzed (400 individuals with the GlobalFiler Express kit and 201 individuals with the VeriFiler Express kit). The locus with the highest power of discrimination (PD) was SE33 (0.9851, 31 alleles), while the least polymorphic locus was D22S1045 (0.75810, 11 alleles). The PE in a similar fashion ranged from 0.2421 (D22S1045) to 0.7818 (SE33). Under the assumption of independence, the combined PD was > 0.9999999999 while the combined PE = 0.9999999933. When comparing the population studied with different populations of Latin America, the greatest Fst genetic distance was obtained with a Venezuelan population (0.052), and the shortest distance was with a Bolivian and Peruvian population (0.004).

Genetic differentiation and overexploitation history of the critically endangered Lehmann’s Poison Frog: Oophaga lehmanni

Species conservation with fragmented and endangered populations must be based on a prior and thorough knowledge of the structure and population dynamics. Oophaga lehmanni is a dendrobatid species endemic of Colombia and is restricted to its type locality. This species has a fragmented distribution and is considered as critically endangered mainly due to habitat destruction and overexploitation. Oophaga lehmanni exhibits phenotypic variation in the dorsal color pattern (red and yellow morphs). We reconstructed the overexploitation history that this species has faced in the last 40 years. In addition, we collected genetic and morphological data for the first time in natural populations to describe genetic diversity between and within populations, and to evaluate morphological and genetic differences between red and yellow morphs. Overexploitation data suggest that more than 80.000 (Min = 60.047–Max = 102.236) frogs were extracted from the field in the last four decades, probably generating the local extirpation or population decline from the type locality. Genetic data showed reduced genetic diversity. Observed heterozygosity (mean ± s.d. = 0.599 ± 0.165) is lower than expected (mean ± s.d. = 0.867 ± 0.082). We did not find differences in body size and heterozygosity between the two morphs; however, individuals analyzed were assigned to two genetic clusters, which corresponded to the O. lehmanni-yellow and O. lehmanni-red. In addition, FST (0.209) and Nei genetic distance (0.18) values indicated genetic differentiation between the two morphs; therefore, red and yellow morphs should be treated as independent management units. This information will help to define appropriate and long-term conservation units, as a useful tool to mitigate the extinction risk of this species.

New insights on intercontinental origins of paternal lineages in Northeast Brazil

BackgroundThe current Brazilian population is the product of centuries of admixture between intercontinental founding groups. Although previous results have revealed a heterogeneous distribution of mitochondrial lineages in the Northeast region, the most targeted by foreign settlers during the sixteenth century, little is known about the paternal ancestry of this particular population. Considering historical records have documented a series of territorial invasions in the Northeast by various European populations, we aimed to characterize the male lineages found in Brazilian individuals in order to discover to what extent these migrations have influenced the present-day gene pool. Our approach consisted of employing four hierarchical multiplex assays for the investigation of 45 unique event polymorphisms in the non-recombining portion of the Y-chromosome of 280 unrelated men from several Northeast Brazilian states.ResultsPrimary multiplex results allowed the identification of six major haplogroups, four of which were screened for downstream SNPs and enabled the observation of 19 additional lineages. Results reveal a majority of Western European haplogroups, among which R1b-S116* was the most common (63.9%), corroborating historical records of colonizations by Iberian populations. Nonetheless, FST genetic distances show similarities between Northeast Brazil and several other European populations, indicating multiple origins of settlers. Regarding Native American ancestry, our findings confirm a strong sexual bias against such haplogroups, which represented only 2.5% of individuals, highly contrasting previous results for maternal lineages. Furthermore, we document the presence of several Middle Eastern and African haplogroups, supporting a complex historical formation of this population and highlighting its uniqueness among other Brazilian regions.ConclusionsWe performed a comprehensive analysis of the major Y-chromosome lineages that form the most dynamic migratory region from the Brazilian colonial period. This evidence suggests that the ongoing entry of European, Middle Eastern, and African males in the Brazilian Northeast, since at least 500 years, was significantly responsible for the present-day genetic architecture of this population.

Major Histocompatibility Complex Class II (DRB3) Genetic Diversity in Spanish Morucha and Colombian Normande Cattle Compared to Taurine and Zebu Populations.

Bovine leukocyte antigens (BoLA) have been used as disease markers and immunological traits in cattle due to their primary role in pathogen recognition by the immune system. A higher MHC allele diversity in a population will allow presenting a broader peptide repertoire. However, loss of overall diversity due to domestication process can decrease a population’s peptide repertoire. Within the context of zebu and taurine cattle populations, BoLA-DRB3 genetic diversity in Spanish Morucha and Colombian Normande cattle was analyzed and an approach to estimate functional diversity was performed. Sequence-based typing was used for identifying 29, 23, 27, and 28 alleles in Spanish Morucha, Nariño-, Boyacá-, and Cundinamarca-Normande cattle, respectively. These breeds had remarkably low heterozygosity levels and the Hardy-Weinberg principle revealed significant heterozygote deficiency. FST and DA genetic distance showed that Colombian Normande populations had greater variability than other phenotypically homogeneous breeds, such as Holstein. It was also found that Spanish Morucha cattle were strongly differentiated from other cattle breeds. Spanish Morucha had greater divergence in the peptide-binding region regarding other cattle breeds. However, peptide-binding region covariation indicated that the potential peptide repertoire seemed equivalent among cattle breeds. Despite the genetic divergence observed, the extent of the potential peptide repertoire in the cattle populations studied appears to be similar and thus their pathogen recognition potential should be equivalent, suggesting that functional diversity might persist in the face of bottlenecks imposed by domestication and breeding.

Molecular characterization of goats from Saudi Arabia using microsatellite markers

This study is undertaken for genetic characterization of local Saudi goat populations for maintaining genetic variability of livestock population. Genomic DNA was extracted from three goat populations namely Ardi, Hollandi and Shami and subjected for genotyping using eighteen recommended microsatellite markers. The average values obtained for number of private alleles, effective number of alleles and different alleles 2.071, 5.343 and 9.389, respectively. The expected and observed heterozygosity values were 0.757 and 0.913, respectively. F- values were 0.081, −0.115, −0.18 and Shannon's Information Index was found to be 1.751. All loci were highly differed from Hardy-Weinburg Equilibrium and an average migrant’s value was 4.302. The maximum value was obtained between Hollandi and Ardi (8.474) and the value was extremely low between Shami and Ardi (2.518). Pairwise population of Fst and Nei's Genetic Distance showed very close relationship between Hollandi and Ardi goat population than between this population with the Shami. STRUCTURE software revealed 3 clusters at K = 3 in goat population. The present findings revealed genetic variations in Hollandi and Ardi populations. Molecular characterization of Saudi goats is important for maintaining and improving genetic resources.