Search Results (29)

The Andalusian Black Cattle (Negra Andaluza) represents a genetic lineage linked to the ancient Eurasian aurochs, shaped by domestication events in the Near East and later introgressions from Italian and North African wild cattle. This study investigates the breed’s anthropological and historical origins, geographical distribution, and genetic structure. Key influences include historical use as draft animals, regional breeding preferences, and gene flow via transhumant routes. The genetic analysis reveals that Córdoba is the principal nucleus, accounting for 448 identified ancestors, compared to 252 in Huelva and 193 in Seville. In Córdoba, contributions of nodal ancestors through inbreeding loops reached a maximum of 0.0447, while mean inbreeding ($\overline{\mathrm{F}}$) was 0.000949 and mean coancestry ($\overline{\mathrm{C}}$) was 0.000475, indicating moderate but geographically structured genetic drift. In contrast, areas with better connectivity showed higher heterogeneity and lower inbreeding contributions. Canonical discriminant analysis (CDA) revealed that the first discriminant function (F1) explained 79.72% of the variation among groups, primarily driven by nodal ancestors and inbreeding loops. Despite these signs of inbreeding, historical transhumance has helped preserve overall genetic diversity. These findings offer essential insights for conservation programs aimed at maintaining both the genetic integrity and adaptive potential of this historically and culturally important breed. Full article

Microhaplotypes (MHs) are a novel class of genetic markers, exhibiting features that position them as an alternative to STRs and SNPs in addressing challenges commonly encountered in forensic investigations. Additionally, MHs can also offer valuable insights for ancestry inference. However, due to the novelty of MHs, extensive research in different global populations is required before implementation in forensic casework and general research. In this study, individuals from Afghanistan and Somalia were characterized with the Ion AmpliSeq™ MH-74 Plex Research Panel previously developed for forensic genetic purposes. A total of 84 Afghan and 89 Somalian samples were sequenced on the Ion GeneStudio™ S5 System. This led to the identification of 32 and 42 single nucleotide variants in the Afghan and Somalian populations, respectively, that were not included in the former MH definitions. Most of the observed variants were considered to be rare occurrences, being observed one or two times in the dataset. The average values of the effective number of alleles (A_e) were 3.7 for Somalia and 3.6 for Afghanistan—pointing to elevated intrapopulation diversities compared to Europeans. Other parameters (H_o, H_e, PIC, PD, and PE) consistently showed higher average values in the Afghans and Somalis compared to the previously studied populations. PCA and STRUCTURE analyses with 1000 Genomes samples assigned the Somalis to a different cluster than the other sub-Saharan African populations. The analyses also showed higher European and East Asian co-ancestry in the Afghans than in the remaining South Asian populations. The capability of the MH-74 plex to address common kinship problems was evaluated through computational simulations, considering generic thresholds differing by one order of magnitude to assess the FDRs. The median LR > 10¹³ for true siblings when the hypotheses ‘full siblings’ and ‘unrelated individuals’ were compared. As expected, the median LRs were much lower for simulated half-siblings and cousins. This work evaluated the forensic potential of MHs in understudied populations. Overall, the studied panel was versatile and capable of being applied in different forensic applications. Full article

Development of any trait-directed selection strategy requires basic knowledge about some important population-specific parameters such as the effective population size $N_e$ and genetic connectedness among flocks. The $N_e$, as an indirect measure of genetic variability, is important for the conservation of the genome, while genetic connectedness is necessary for unbiased across-flock genetic evaluation. The average number of full generations (NFG) in the reference population of the Pag sheep under selection for dairy traits was 3.05. The $N_e$ estimated from individual coancestry rate $∆C_{ij}$ in the last generation was 127 animals, and the average prediction error variance of the difference in EBVs between animals belonging to different flocks ($\overline{{PEVD}_{i^{\prime },j^{\prime } }}$) was 0.81. Although conceptually different, these two population genetic parameters may be related in the populations under selection. Although it is difficult to prove this hypothesis, we decided to test it by regressing the partial (generational) estimates of $N_e$ on $\overline{{PEVD}_{i^{\prime },j^{\prime } }}$. It was estimated that $∆\overline{{PEVD}_{i^{\prime },j^{\prime } }}$ of −0.01 was accompanied by $∆N_e$ of +5.5 animals. The results suggest that strengthening genetic connectedness among flocks in populations might have a positive impact on genetic diversity; however, more research is needed before generalization. Full article

Montbeliarde dairy cattle were introduced in Ecuador with the aim of ameliorating the production performance of other cattle breeds. The aim was to analyze the reproductive performance, demographic structure, inbreeding, and genetic diversity of Montbeliarde cattle obtained by absorption crossing. Official pedigree records from the Ecuadorian Montbeliarde Association were used. The total population was divided into seven populations: (i) historical (all individuals), (ii) 1999–2003, (iii) 2004–2008, (iv) 2009–2013, (v) 2014–2018, (vi) 2019–2023 (current), and (vii) reference (individuals with known parents). Demographic structure variables analyzed: pedigree completeness index (PCI), number of equivalents (GEqu), complete (GCom) and maximum (GMax) generations, and generation interval (GI). Inbreeding-derived variables analyzed: inbreeding (F), inbreeding increment (ΔF), average relatedness (AR), co-ancestry (C), non-random mating (α), effective population size (Ne), and genetic conservation index (GCI). Gene origin probability/genetic diversity variables analyzed: number of founders (f), effective number of founders (fe) and ancestors (fa), number of equivalent genomes (fg), fe/fa and fg/fa ratio, and DG losses. The databases were analyzed by ENDOG, POPREP, and CPC software. PCI in the historical population compared to the current population decreased from 72.95 to 65.87% (sire/dam pathway), while the GI decreased from 7.17 to 3.08 years when the historical and current populations were compared. Dam reproductive efficiency increased over time. Moreover, F = ~1%, AR = 2.06%, ΔF = 0.22%, C = 1.03%, α = −0.0077, GCI = 3.12, and Ne = 58 values were obtained. Gene origin probability in the reference population was f = 439, fa = 37, fe = 71.64, fg = 23.43, and fg/fe = 0.33, showing a GD loss due to unequal contribution of founders (0.55%) and bottleneck and genetic drift (4.25%). In conclusion, the Ecuadorian Montbeliarde cattle population displayed a relatively low diversity and high genetic relationship. Inbreeding levels increased while Ne values decreased over time. The introduction of new purebred bloodlines could be important to minimize the inbreeding levels ensuring the long-term conservation of this breed and minimizing GD loss. Full article

Revealing the relationship between the mating system (i.e., the outcrossing/inbreeding degree) and the fitness of seeds in tree species under wild conditions is essential for understanding the ecological adaptability and evolutionary stability of the species. This study collected open-pollinated seeds from seven wild populations of Pinus yunnanensis var. tenuifolia that exhibited fragmentation in the Nanpan–Hongshui River basin, an ecologically fragile area in China. The seeds and sprouts (germinated seeds) from 20 families were genotyped (24 seeds and 24 sprouts per family) using twelve microsatellite loci to reveal the genetic diversity, mating status, and effect of inbreeding on the three seed quality indicators (thousand-seed weight, germination rate, and germination potential). The three seed quality indicators differed significantly between families (p < 0.001). Higher values of genetic diversity (except the observed heterozygosity) were observed in the sprout group than those in the seed group. Families from different populations showed a notable genetic differentiation (Φst = 0.12), and a large part of families from the common populations had a high degree of coancestry, which signified that the current habitat fragmentation is limiting gene flow between populations. High levels of outcrossing rates (tm) were observed in both the seed group (t_m = 0.974) and the sprout group (t_m = 0.978), indicating that a low proportion of seeds were self-fertilized. Although there was a slightly higher single outcrossing rate (t_s = 0.888) and a lower proportion of biparental inbreeding (t_m − t_s = 0.077) in sprouts compared to the seeds (t_s = 0.871, t_m − t_s = 0.091), indicating that a part of inbred seeds were purged during the germination stage, curve fitting between the outcrossing rate and seed quality indicators showed that a certain degree of biparental inbreeding (t_s between 0.89 and 0.91 and t_m − t_s between 0.09 and 0.11) did have a positive effect on seed germination ability. This highlights that excessive inbreeding or outbreeding seems to be unfavorable to seed viability. The peculiar relationship between seed viability and the mating system in P. yunnanensis var. tenuifolia was likely an evolutionary consequence of a trade-off between the nature of mixed mating and its specific ecological niche. Full article

The inference of biogeographical ancestry (BGA) can assist in police investigations of serious crime cases and help to identify missing people and victims of mass disasters. In this study, we evaluated the typing performance of 56 ancestry-informative SNPs in 177 samples using the ForenSeq™ DNA Signature Prep Kit on the MiSeq FGx system. Furthermore, we compared the prediction accuracy of the tools Universal Analysis Software v1.2 (UAS), the FROG-kb, and GenoGeographer when inferring the ancestry of 503 Europeans, 22 non-Europeans, and 5 individuals with co-ancestry. The kit was highly sensitive with complete aiSNP profiles in samples with as low as 250pg input DNA. However, in line with others, we observed low read depth and occasional drop-out in some SNPs. Therefore, we suggest not using less than the recommended 1ng of input DNA. FROG-kb and GenoGeographer accurately predicted both Europeans (99.6% and 91.8% correct, respectively) and non-Europeans (95.4% and 90.9% correct, respectively). The UAS was highly accurate when predicting Europeans (96.0% correct) but performed poorer when predicting non-Europeans (40.9% correct). None of the tools were able to correctly predict individuals with co-ancestry. Our study demonstrates that the use of multiple prediction tools will increase the prediction accuracy of BGA inference in forensic casework. Full article

The Turopolje pig is a fatty-type pig breed created during the Middle Ages in the Turopolje region in Central Croatia. Although the population of the Turopolje pig is stable today, this breed is still one of the endangered breeds that are severely threatened by inbreeding. The aim of this work was to evaluate the genetic diversity parameters of the recent Turopolje pig population in Croatia and to consider mating strategies to limit the increase in inbreeding in the population using algorithms within an optimal contribution selection frame. The pedigree of 1155 individuals was analysed. In addition to the basic pedigree structure, the following population parameters were analysed: average coefficient of inbreeding; mean rate of increase in coancestry; increase in coancestry between any individuals; effective population size. Based on obtained parameters, mating optimization using estimated kinship between candidates in several scenarios was carried out, restricting maximal kinship between candidates on a minimal possible value 0.07, as the least possible level of kinship, candidates on a value of 0.10, and candidates on a value of 0.25. The average inbreeding coefficient (F) in the population was 0.03, while the average F of inbred animals was 0.10. The effective population size obtained from pedigrees based on the increase in coancestry (0.17) was 29.14. Mating plans were created from 5 active boars and 120 sows in different scenarios with constraint on the level of kinship between candidates. The least possible level of kinship was 0.07, and no available solutions were under this level. With the increase in the allowed kinship between candidates, the level of inbreeding increased from 0.01 to 0.06 in the next generation. Under practical conditions, mating between ideal individuals in local pig populations is not always possible, and the use of optimisation algorithms allows alternative mating within existing populations to be considered. Finally, this approach opens up the possibility of potentially improving sustainable breeding through selection by considering breeding values for economically important traits. This approach can help to differentiate the Turopolje pig breed from other commercial and local breeds, e.g., for meat quality traits. Full article

The Amazonian native tree species Parkia multijuga has potential silvicultural characteristics that can be utilized to productive plantations. Understanding its mating system is necessary to delineate the methods for the breeding of the species, the collection of seeds for conservation, and the use of seedlings for production plantations. The aim of this study is to evaluate the mating system and population genetic diversity of P. multijuga, using molecular markers. The DNA of 221 plants was extracted and genotyped with nine microsatellite loci using capillary electrophoresis in an automated DNA sequencer. The estimates for single and multilocus crossing rates were 0.998 and 1.0, respectively. The paternity correlation was low (${\widehat{r}}_{p\left(m\right)}$ = 0.307). The fixation index (f) showed values below zero, indicating an excess of heterozygotes. The cluster number K = 2 shows a better grouping among families for genetic structure. P. multijuga families consist mainly of half-sibs, and the reproductive strategy of the species is allogamy. Full article

The Wright–Fisher model predicts that the ratio of effective population size ($N_e$) to actual population size ($N$) is <1.0 due to inbreeding and random drifts under constant population sizes. However, social structure may prevent inbreeding and result in outbreeding through coancestry, causing the $N_e/N$ ratio to exceed 1.0. We integrated three years of data on seasonal population fluctuations and population genetics of group-living Daurian pikas (Ochotona dauurica) to test the prediction of >1.0 $N_e/N$ ratio for social small mammals. We estimated biweekly pika population sizes using capture–recapture data from May 2010 to October 2012. We genotyped all captured pikas in each of the three years with 11 microsatellite markers. We estimated pika effective population sizes for 2010–2011, 2011–2012, and 2010–2012, respectively, using the temporal methods with the program MLNe. Pika populations underwent a 75% decline in the summer of 2010 and exhibited relatively constant seasonal fluctuations from 2011 to 2012. Bayesian clustering with program STRUCTURE identified two distinct genetic clusters for the pikas of 2010 and 2011–2012, respectively. The $N_e/N$ ratios of the pikas were 0.46, 1.13, and 0 54 for 2010–2011, 2011–2012, and 2010–2012, respectively. Our findings partially support our hypothesis with the $N_e/N$ ratio being >1.0 from 2011 to 2012. The dramatic population decline in the summer of 2010 probably disrupted the social structure of pikas, which subsequently increased the rate of genetic diversity losses. Re-establishments of the social structure during 2011 and 2012 probably restored the outbreeding of pikas like in other social mammals. Full article

Fertility variation, defined as a difference in the ability to create progeny (i.e., reproductive success) among individuals, was reviewed using the related available theoretical and practical literature in an attempt to contribute to and improve future studies on the subject. Fertility variation is a useful guide for various purposes such as gene conservation, seed production programs, forest genetic resource (i.e., seed sources) management, other forestry practices (e.g., regeneration), and evolutional and physiological studies. Many papers and proceedings have been published, including both theoretical and practical approaches, on how fertility variation has improved in the last two decades. Large variations in fertility were widely reported among populations within species and among species. We reviewed the literature and combined our diverse knowledge to examine fertility variations and their linkage parameters. Fertility variations and their related parameters (e.g., gene diversity, status number, effective parent number, parental–balance curves) estimated based on reproductive characteristics have been studied for many years using easy and cheap surveys that are used for different purposes in forest sciences. Their importance is increasing and their use is becoming more widespread because of these advantages, leading to improvements in research papers. While many research papers have recently been published on fertility variations and linkage parameters, a review paper has not been published to date. Therefore, a review paper is needed based on a literature survey and unpublished experience, as a guide for future studies. Full article

In most Western European societies, surnames pass from generation to generation and in cases where surnames are shared by fathers to children, the Y chromosome passes down from fathers to male offspring in the same way as surnames do. The aim of this study was to ascertain the patrilineal relationship between individuals with the surname “Castilla” and their respective Y-chromosome haplotypes. The toponymic surname “Castilla” is part of the Spanish royal family. Genealogical studies of this surname have allowed the formulation of different hypotheses about its origin, most of which were centered in Burgos. To shed some light on the origin of the surname Castilla and to investigate the possible co-ancestry behind the living carriers of this surname, markers located in the Y chromosome-specific region were analyzed in a sample of 102 men whose paternal surname was Castilla. The study aimed to establish the minimum number of founders and the expansion time of the lineages from our sample. Two major haplogroups were identified: R1b and E1b1b-M81. The high frequency of the E1b1b-M81 haplogroup in comparison to that of the general Spanish population, its low haplotype diversity, and its young TMRCA (323+/− 255 years CE) are compatible with the historical timing of the obligation to use surnames. However, the coincidence of the most common haplogroup in the Castilla sample and the most frequent haplogroup in the Spanish general population, R1b, makes it difficult to identify founder haplotypes/haplogroups in the history of the Castilla surname. Full article

Ship sturgeon (Acipenser nudiventris) is a critically endangered fish that is listed on the International Union for Conservation of Nature’s Red List of Threatened Species. Sixteen individuals from the Chinese section of the Ili River were genotyped using genome re-sequencing technology. By applying a genomic relatedness estimation with 1,527,694 genome-wide SNP markers, we found that the coancestry coefficients showed a high level of relatedness between individuals. The effective population sizes over 500 generations were estimated, and this showed that the effective population sizes began to dramatically decline from about 14,840 to 171 individuals when going back four generations from the current population. Artificial reproduction techniques guided by genomic relatedness may be a valuable approach to the conservation of this critically endangered fish species. Full article

The Manila clam (Ruditapes philippinarum) is one of the most commercially important bivalves along the coast of China. With the continuous expansion of clam farming scale, it may lead to some serious problems, including loss of genetic variation, inbreeding depression, and reduced effective population size (N_e). In the present study, eleven microsatellite markers were used to investigate the genetic diversity and differentiation among 13 clam populations along the coast of China. As a result, 150 alleles were detected according to the genotyping results of eleven microsatellite loci. The observed heterozygosity (H_o) was estimated to be ranging from 0.437 to 0.678, while the expected heterozygosity (H_e) was calculated to be varying from 0.587 to 0.700. F_st values between populations ranged from 0.0046-0.1983. In particular, the Laizhou population had the highest genetic variability, which was significantly different from the others (all F_st values > 0.1). For all the clam populations, there was no significant linear regression between genetic and geographic distance, indicating that these populations do not follow a pattern of isolation by distance (IBD). Genetic structure was estimated according to NJ, principal coordinates (PCoA), and structure-based clustering. Estimates of effective population size range from dozens to thousands among different populations, based on linkage-disequilibrium and molecular coancestry methods. The results reveal the genetic diversity of clams and verify the hypothesis that clam population differentiation may be influenced by the mode of southern breeding and northern culture, providing guiding information for natural resource conservation and genetic breeding of clams. Full article

The complex genomic composition of allopolyploid plants leads to morphologically diverse species. The traditional taxonomical treatment of the medium-sized, hexaploid shrub willows distributed in the Alps is difficult based on their variable morphological characters. In this study, RAD sequencing data, infrared-spectroscopy, and morphometric data are used to analyze the phylogenetic relationships of the hexaploid species of the sections Nigricantes and Phylicifoliae in a phylogenetic framework of 45 Eurasian Salix species. Both sections comprise local endemics as well as widespread species. Based on the molecular data, the described morphological species appeared as monophyletic lineages (except for S. phylicifolia s.str. and S. bicolor, which are intermingled). Both sections Phylicifoliae and Nigricantes are polyphyletic. Infrared-spectroscopy mostly confirmed the differentiation of hexaploid alpine species. The morphometric data confirmed the molecular results and supported the inclusion of S. bicolor into S. phylicifolia s.l., whereas the alpine endemic S. hegetschweileri is distinct and closely related to species of the section Nigricantes. The genomic structure and co-ancestry analyses of the hexaploid species revealed a geographical pattern for widespread S. myrsinifolia, separating the Scandinavian from the alpine populations. The newly described S. kaptarae is tetraploid and is grouped within S. cinerea. Our data reveal that both sections Phylicifoliae and Nigricantes need to be redefined. Full article

Accuracy of predicted breeding values (PBV) for low heritability traits may be increased in early generations by exploiting the information available in correlated traits. We compared the accuracy of PBV for 10 correlated traits with low to medium narrow-sense heritability ($h^2)$ in a genetically diverse field pea (Pisum sativum L.) population after univariate or multivariate linear mixed model (MLMM) analysis with pedigree information. In the contra-season, we crossed and selfed S₁ parent plants, and in the main season we evaluated spaced plants of S₀ cross progeny and S₂₊ (S₂ or higher) self progeny of parent plants for the 10 traits. Stem strength traits included stem buckling (SB) ($h^2$ = 0.05), compressed stem thickness (CST) ($h^2$ = 0.12), internode length (IL) ($h^2$ = 0.61) and angle of the main stem above horizontal at first flower (EAngle) ($h^2$ = 0.46). Significant genetic correlations of the additive effects occurred between SB and CST (0.61), IL and EAngle (−0.90) and IL and CST (−0.36). The average accuracy of PBVs in S₀ progeny increased from 0.799 to 0.841 and in S₂₊ progeny increased from 0.835 to 0.875 in univariate vs MLMM, respectively. An optimized mating design was constructed with optimal contribution selection based on an index of PBV for the 10 traits, and predicted genetic gain in the next cycle ranged from 1.4% (SB), 5.0% (CST), 10.5% (EAngle) and −10.5% (IL), with low achieved parental coancestry of 0.12. MLMM improved the potential genetic gain in annual cycles of early generation selection in field pea by increasing the accuracy of PBV. Full article