Heterozygote Deficit Research Articles

Genetic Diversity and Relatedness among Different Four Cattle Breeds Reared in Rajasthan

Genetic diversity and relationship between population of one hundred nine individuals from four cattle breeds i.e. Rathi, Tharparkar, Gir and Kankrej were studied using 18 microsatellite markers, proposed by FAO and ISAG. A total of 144, 135, 147 and 155 alleles were identified across 18 microsatellite loci in Rathi, Tharparkar, Gir and Kankrej cattle, respectively. The heterozygosity was found higher in Kankrej breed with the value of 0.62±0.29. The Mean value of F-statistics significantly deviated from zero indicating that breeds are well separated. The present study indicates a significant deficit of heterozygotes in studied cattle breeds. The Nei’s Genetic distance analysis of the four cattle breed population revealed close genetic similarity between Rathi-Tharparkar in comparison to other breeds with maximum genetic distance between Tharparkar and Gir. Phylogenetic analysis based on UPGMA method further supported close genetic relationship between Rathi-Tharparkar as they clustered in one group.

Fine-scale genetic structure in populations of the spring ephemeral herb Megaleranthis saniculifolia (Ranunculaceae)

Fine-scale genetic structure (FSGS) in plants occurs primarily through restricted seed dispersal. Analyses of FSGS have been used retrospectively to infer seed dispersal and other ecological processes. The spring ephemeral Megaleranthis saniculifolia, endemic to Korea, is insect-pollinated and has no special seed dispersal mechanism, and its seedling recruitment is quite low. Given these ecological and life-history traits, we expect that there would be significant FSGS in juveniles, which would persist into adult stage. Since M. saniculifolia is self-compatible and many adults produce 2–3 inflorescences, we expect considerable inbreeding. To test these predictions, we used allozyme-based Sp statistics to compare two undisturbed populations on Mt. Deogyu (DEO) and Mt. Taebaek (TAE), as well as between juveniles (J) and adults (A) stages. We also measured genetic diversity and inbreeding in each population. The two populations exhibited significant FSGS in both life stages. Although the strength of FSGS was reduced with increasing stage (J, Sp = 0.0313; A, Sp = 0.0178 in DEO and J, Sp = 0.0502; A, Sp = 0.0286 in TAE), differences in FSGS between stages and between populations were not significant. Within-population genetic diversity (mean %P = 27.0, A = 1.27, He = 0.116) was relatively low and comparable to reference values for both endemic and narrowly-distributed plant species. Genetic differentiation between sites, however, was high (FST = 0.465), and the two populations exhibited a significant deficit of heterozygotes (mean FIS = 0.289), primarily due to selfing and biparental inbreeding (effective selfing rate was ∼0.40). Our results revealed that the magnitude and spatial scale of FSGS in M. saniculifolia is strong and does not differ significantly with life-history stage. The strong FSGS, low within-population genetic variation, high between-population genetic differentiation, and high inbreeding are consistent with the species’ limited seed dispersal and a mixed mating system.

Revisiting FIS, FST, Wahlund Effects, and Null Alleles.

Null alleles and Wahlund effects are well known causes of heterozygote deficits in empirical population genetics studies as compared to Hardy-Weinberg genotypic expectations. Some authors have theoretically studied the relationship of Wright's FIS computed from subsamples displaying a Wahlund effect and FST before the Wahlund effect, as can occasionally be obtained from populations of long-lived organisms. In the 2 subsample case, a positive relationship between these 2 parameters across loci would represent a signature of Wahlund effects. Nevertheless, for most organisms, getting 2 independent subsamples of the same cohort and population, one with a Wahlund effect and the other without, is almost never achieved and most of the time, empirical population geneticists only collect a single sample, with or without a Wahlund effect, or with or without null alleles. Another issue is that null allele increase FIS and FST altogether and thus may also create such correlation. In this article, I show that, for organisms collected in a single sample, which corresponds to the most common situation, Wahlund effects and null alleles affect the values of both FIS and FST though in the opposite direction. I also show that Wahlund effect produces no or weak positive correlation between the 2 F-statistics, while null alleles generate a strong positive correlation between them. Variation of these F-statistics is small and even minimized for FST under Wahlund effects as compared to null alleles. I finally propose a determination key to interpret data with heterozygote deficits.

Variabilidad genética del cerdo Congo Santandereano mediante marcadores microsatelite

El cerdo Congo Santandereano es un recurso zoogenético de importancia para la seguridad alimentaria y la economía campesina propio del departamento de Santander, Colombia. Se determinó su variabilidad genética mediante la genotipificación de 12 marcadores microsatélite, reportados por la FAO y la ISAG. Se recolectaron 37 muestras de sangre porcina. El ADN fue extraído mediante el kit DNA 2000 de Corpogen®, y cuantificado por fluorometria (Qubit Fluorometer Invitrogen®). Los microsatélites se amplificaron mediante PCR simple, para la genotipificación se sometieron los amplificados a electroforesis en cámara vertical en geles de poliacrilamida. Mediante el programa Genetix® se calculó la heterocigosidad observada (Ho) y esperada (He), el número de alelos para cada locus, las frecuencias alélicas y el coeficiente de endogamia Fis; con la herramienta Toolkit microssatélite de Excel® se calcularon los índices polimórficos (PIC). Los 12 microsatélites resultaron polimórficos y se detectó un total de 52 alelos. El número medio de alelos encontrado en el cerdo Congo fue de 4,3. La He varió entre un mínimo de 0,42 para los marcadores S009 y SW240 y un máximo de 0,76 para el marcador CGA1. La heterocigosidad media observada fue de 0,35, la mayoría de los marcadores utilizados resultaron muy informativos de variabilidad genética con valores de PIC superiores a 0,5. El índice de endogamia (FIS 0,5) revela un alto déficit de heterocigotos . Estos hallazgos sugieren baja variabilidad genética del cerdo Congo, con una tendencia al incremento de consaguinidad, posiblemente relacionada con un tamaño poblacional reducido.

A fig tree in a concrete jungle: fine-scale population genetic structure of the cluster fig Ficus racemosa in an urban environment

Urban vegetation is an essential requirement in cities for mitigating pollution, heat island effects and providing food and shelter to urban fauna. Efforts to conserve and augment green cover in cities, however, often lack data on the genetic diversity of urban trees, which could be crucial to the success of such programmes. We investigate the population genetics of the cluster fig Ficus racemosa, which occurs naturally in Indian cities and is a keystone species for urban fauna. Genetic analysis of 51 F. racemosa trees in urban Bangalore, India, shows no evidence of inbreeding; the overall inbreeding coefficient (F is ) across 12 microsatellite markers (0.0366) was non-significant with no evidence of heterozygote deficit. Spatial genetic structure (SGS) analysis of 47 trees showed an overall negative relationship between kinship coefficient and spatial distance, with strong SGS at distances <1 km. The absence of heterozygote deficit is likely due to the fig’s obligate mutualistic association with fig wasps which pollinate their flowers even across long distances. However, the strong SGS at short distances could result from clumped seed dispersal close to natal trees. Therefore, the pattern of population genetics for F. racemosa from urban Bangalore likely results from short-distance seed dispersal and long-distance pollen flow. Despite the scattered and fragmented nature of green areas within cities, these gene mobility factors maintain robust population genetics in F. racemosa even at low population densities. The same may not apply for Ficus species that are planted as vegetative cuttings in cities and therefore may have limited genetic diversity.

Inbreeding in the exploited limpet Patella aspera across the Macaronesia archipelagos (NE Atlantic): Implications for conservation

The genetic erosion of populations exposed to human exploitation plays a detrimental role on a species ability to adapt to changing environmental conditions. The Macaronesia (NE Atlantic) endemic limpet Patella aspera (Roding 1798) has been subject to overexploitation throughout its geographic distribution. We analysed 841 limpet specimens from eleven islands across the archipelagos of Azores, Madeira and Canaries. Results from 11 nuclear microsatellite markers showed significant population structure between populations from Azores and populations from Madeira and Canaries, and absence of current or historic gene flow between these. M-ratios showed that both population clusters have experienced demographic changes over time. Heterozygote deficits were common across populations, which can be better accounted for by inbreeding than by null alleles or Wahlund effect. Such levels of inbreeding are likely a consequence of a significant reduction of reproductive units due to decades of intensive exploitation. As a sequential protandrous hermaphrodite, the size-selective harvesting of larger individuals likely fosters unbalanced sex-ratios and a consequent reproductive shortage. A recent compensatory hypothesis suggests that males are compensating the removal of larger females by undergoing sex change earlier and presumably at smaller sizes, as an adaptive response of the species under high size-biased fishing pressure. Despite such response, a dramatic reduction of Ne emerging from a large variation in the reproductive success due to overfishing and artificial genetic drift, can simply explain the inbreeding scenario observed in this Macaronesia endemic key species. This study provides valuable insights for management and conservation of P. aspera throughout Macaronesia.

Genome-Wide SNP Discovery and Analysis of Genetic Diversity in Farmed Sika Deer (Cervus nippon) in Northeast China Using Double-Digest Restriction Site-Associated DNA Sequencing.

Sika deer are an economically valuable species owing to their use in traditional Chinese medicine, particularly their velvet antlers. Sika deer in northeast China are mostly farmed in enclosure. Therefore, genetic management of farmed sika deer would benefit from detailed knowledge of their genetic diversity. In this study, we generated over 1.45 billion high-quality paired-end reads (288 Gbp) across 42 unrelated individuals using double-digest restriction site-associated DNA sequencing (ddRAD-seq). A total of 96,188 (29.63%) putative biallelic SNP loci were identified with an average sequencing depth of 23×. Based on the analysis, we found that the majority of the loci had a deficit of heterozygotes (FIS >0) and low values of Hobs, which could be due to inbreeding and Wahlund effects. We also developed a collection of high-quality SNP probes that will likely be useful in a variety of applications in genotyping for cervid species in the future.

Isolation and Characterization of 18 Polymorphic Microsatellite Loci for the Endangered New Zealand Black-Fronted Tern (Chlidonias albostriatus)

Abstract. Eighteen polymorphic microsatellite loci were isolated and characterized from the endangered Black-fronted Tern (Chlidonias albostriatus), a species endemic to New Zealand. The loci were initially tested on seven individuals spanning the entire breeding range and then for a larger dataset of 345 samples covering 30 colonies from throughout the species' range. The number of alleles per loci ranged from 4 to 24, and observed and expected heterozygosity ranged between 0.46 and 0.95 and 0.45 to 0.86, respectively. One locus showed significant heterozygote deficit and appears to be sex-linked. The similar annealing temperatures across loci and the wide fragment sizes allowed multiplex polymerase chain reaction and rapid multilocus genotyping. The microsatellite markers will be useful tools for further investigation into the genetic diversity, population structure and effective population size of this endangered species and for informing conservation management.

Genetic variability of Prochilodus lineatus in artificial and semi-natural reproduction

Prochilodus lineatus is a South American fish of great economic and social importance that is impacted by high fishing pressure. Restocking programmes have tried to be effective in recovering natural populations; however, genetic and reproductive methodologies are necessary to make feasible the survival of released fingerlings. The genetic variability of P. lineatus subjected to semi-natural and artificial reproduction was evaluated. Caudal fin samples from 25 breeders subjected to an artificial reproduction were collected at different sex ratios (1♂:1♀ and 2♂:1♀), and 138 fingerlings originated from these spawning. Similarly, samples were collected from 10 breeders (1♂:1♀) subjected to a semi-natural reproduction, and 70 fingerlings were generated from this spawning. Ten microsatellite loci were evaluated, producing 142 alleles. High interpopulation variability for broodstock and fingerlings was observed in both reproductive systems. A deficit of heterozygotes through the inbreeding coefficient (Fis) was obtained. Moreover, a deviation in the Hardy–Weinberg equilibrium of the fingerlings in both systems was detected. Fst values indicated a moderate genetic differentiation in 1:1 artificial reproduction system and low differentiation in 2:1 artificial and 1:1 seminatural reproduction system. Despite the high genetic variability, genetics analyses in the next generations of fingerlings will be necessary considering the likelihood of a decrease in genetic variability.

Genetic diversity and structure in a major Brazilian annatto (Bixa orellana) germplasm bank revealed by microsatellites and phytochemical compounds

Annatto (Bixa orellana L.) is a tropical crop indigenous to the Americas, probably Amazonia. Annatto is commercially valuable in the food and cosmetics industries as a natural dye used instead of synthetic dyes. In addition, annatto contains other important substances for human health, such as geranylgeraniol, tocotrienols and other carotenoids. The aim of the present study was to evaluate the genetic diversity of 63 accessions from the annatto germplasm bank at the Agronomic Institute (IAC), Sao Paulo, Brazil, using four phytochemical compounds and 16 microsatellite markers. Significant variation was observed for the phytochemical compounds, ranging from 2 to 7.31 g (100 g dry matter—DM)−1 for bixin, 2.14–7.11 g (100 g DM)−1 for lipids, 0.25–1.05 g (100 g DM)−1 for tocotrienols, and 0.49–2.61 g (100 g DM)−1 for geranylgeraniol content. A total of 73 alleles was observed in the molecular characterization with 16 microsatellite loci. We found higher expected heterozygosity than observed heterozygosity for all loci, indicating strong deficits of heterozygotes. For both molecular and phytochemical compounds, cluster and PCoA analyses tended to separate the accessions from Rondonia, northern Brazil, with only a few exceptions, from the Southwestern accessions. The same two groups were found in the Bayesian analysis with molecular data. Rondonia accessions showed higher values for all the phytochemical compounds and higher levels of genetic diversity. Some accessions presented bixin levels well above the average and are promising materials to be used in genetic improvement programs.

Does peripheral dislodgement contribute to heterozygote deficiencies in blue mussels?

AbstractDifferential loss of heterozygous individuals that move to the periphery of mussel aggregations, where they are at greater risk for dislodgement, has been proposed as an explanation for observed heterozygote deficiencies in blue mussels. To test the dislodgement hypothesis, correlations between heterozygosity and mussel motility, as well as characteristics of byssogenesis and byssal thread attachment strengths, were determined in a wild and a farmed population of blue mussels (Mytilus edulis) from New Hampshire, USA. Although both populations exhibited a heterozygote deficit as measured by three microsatellite loci, no relationship was found between heterozygosity and increased motility in either population. Similarly, no relationship was found between heterozygosity and byssogenesis or attachment strength. Hence, differential dislodgement is highly unlikely as a possible contributor to the loss of heterozygous individuals.

Genetic diversity of tambaqui broodstocks in stock enhancement programs.

Natural populations of tambaqui (Colossoma macropomum) have significantly decreased in recent decades especially due to human extraction activities. So that the environmental impact may be reduced, the restocking of fish and increase in fish production are enhanced. Genetic evaluations using molecular markers are essential for this purpose. Current study evaluates the genetic variability of two tambaqui broodstocks used in restocking programs. Sixty-five samples (33 samples from broodstock A and 32 samples from broodstock B) were collected. DNA was extracted from caudal fin samples, with the amplification of four microsatellite loci: Cm1A11 (EU685307) Cm1C8 (EU685308) Cm1F4 (EU685311) and Cm1H8 (EU685315). Fourteen alleles in the stock of broodstock A were produced, five alleles for Cm1A11 locus (230, 255, 260, 270 and 276 bp), three alleles Cm1C8 (239, 260, and 273 bp), two alleles Cm1F4 (211 and 245 bp), four alleles for Cm1H8 (275, 290, 320 and 331 bp) and two unique alleles were found for Cm1A11 loci (alleles 270 and 276 bp) and Cm1H8 (alleles 275 and 331 bp). In broodstock B, ten alleles were produced, the same alleles of the first stock except for alleles 270 and 276 bp in Cm1A11 locus and 275 and 331 bp in Cm1H8 locus. Broodstock A revealed low frequency alleles in Cm1A11 loci, Cm1C8, Cm1F4 and Cm1H8, whereas broodstock B had no locus with low allelic frequency. Loci Cm1A11, Cm1C8 and Cm1H8 exhibited significant deficit of heterozygotes in both broodstocks, revealing changes in Hardy-Weinberg equilibrium. Genetic diversity between stocks was 0.1120, whilst genetic similarity was 0.894, with FST rate = 0.05, and Nm = 3.93, indicating gene flow between the two broodstocks. Results show that broodstocks are genetically closely related, with no great genetic variability. Strategies such as a previous genetic analysis of breeding with its marking, use of a large Ne crossing between the most genetically divergent specimens, and the introduction of new genetic material to broodstocks may maximize genetic diversity and minimize inbreeding within the next generation.

Genetic diversity of tambaqui broodstocks in stock enhancement programs

Natural populations of tambaqui (Colossoma macropomum) have significantly decreased in recent decades especially due to human extraction activities. So that the environmental impact may be reduced, the restocking of fish and increase in fish production are enhanced. Genetic evaluations using molecular markers are essential for this purpose. Current study evaluates the genetic variability of two tambaqui broodstocks used in restocking programs. Sixty-five samples (33 samples from broodstock A and 32 samples from broodstock B) were collected. DNA was extracted from caudal fin samples, with the amplification of four microsatellite loci: Cm1A11 (EU685307) Cm1C8 (EU685308) Cm1F4 (EU685311) and Cm1H8 (EU685315). Fourteen alleles in the stock of broodstock A were produced, five alleles for Cm1A11 locus (230, 255, 260, 270 and 276 bp), three alleles Cm1C8 (239, 260, and 273 bp), two alleles Cm1F4 (211 and 245 bp), four alleles for Cm1H8 (275, 290, 320 and 331 bp) and two unique alleles were found for Cm1A11 loci (alleles 270 and 276 bp) and Cm1H8 (alleles 275 and 331 bp). In broodstock B, ten alleles were produced, the same alleles of the first stock except for alleles 270 and 276 bp in Cm1A11 locus and 275 and 331 bp in Cm1H8 locus. Broodstock A revealed low frequency alleles in Cm1A11 loci, Cm1C8, Cm1F4 and Cm1H8, whereas broodstock B had no locus with low allelic frequency. Loci Cm1A11, Cm1C8 and Cm1H8 exhibited significant deficit of heterozygotes in both broodstocks, revealing changes in Hardy-Weinberg equilibrium. Genetic diversity between stocks was 0.1120, whilst genetic similarity was 0.894, with FST rate = 0.05, and Nm = 3.93, indicating gene flow between the two broodstocks. Results show that broodstocks are genetically closely related, with no great genetic variability. Strategies such as a previous genetic analysis of breeding with its marking, use of a large Ne crossing between the most genetically divergent specimens, and the introduction of new genetic material to broodstocks may maximize genetic diversity and minimize inbreeding within the next generation.

GENETIC VARIATION IN INDIGENOUS TURKEY POPULATIONS IN SOUTH WEST NIGERIA

The study was carried out to assess the genetic variation in indigenous turkey populations in South West Nigeria using seven protein markers: Hemoglobin (Hb), Albumin (Alb), Transferin (Tf), Esterase-1 (Es-1), Alkaline phosphatase (ALP), Carbonic anhydrase (CA), and Esterase-3 (Es-3).. A total of 97 turkey birds from Ibadan, Ijebu Ode and Akure were purposively sampled. Separation of plasma and red cell proteins were determined on cellulose acetate electrophoresis to estimate the genetic variability within and among the populations. The degree of heterozygosity, deviation from Hardy-Weinbergs Equilibrum (HWE), FIS, and FST values were estimated. From a total of 7 loci analyzed, six were found to be polymorphic in all the populations sampled while Es-1 was monomorphic. Two codominant alleles which controlled three different genotypes were observed at each polymorphic loci. Deviations from Hardy Weinberg equilibrium and a deficiency of heterozygotes were observed in all the populations. Average heterozygosities ranged between 0.13 and 0.20, heterozygote deficit FIT was estimated at 0.5784 while within breed deficit as evaluated by FIS ranged from 0.38 to 0.56. The fixation index FST revealed that genetic diversity within the studied population was moderately differentiated. Genetic distance among the populations quantified through calculation of Nei genetic distance ranged from 0.037 - 0.109. The result obtained may be used as an initial guide in defining objectives for future investigations of genetic integrity and developing conservation strategies for Nigeria indigenous turkeys.

Variación génica intrapoblacional del caracol gigante africano (Achatina fulica) en el Valle del Cauca

Objetivo. Evaluar la variación genética intrapoblacional de A. fulica en el Valle del Cauca. Materiales y métodos. Se amplificaron diez loci microsatélites de muestras obtenidas en ocho municipios del Departamento. Se estimaron las frecuencias alélicas y descriptores de la diversidad genética intrapoblacional y se discriminó mediante un análisis bayesiano la cantidad de agrupaciones presentes en la zona de estudio. Resultados. Se identificaron dos agrupaciones en el Valle del Cauca (p&gt;50%): una conformada por los individuos de los municipios del Norte y Centro, otra por los municipios del Sur y Occidente. Estas agrupaciones, fueron genéticamente diferentes (FST0.16; p&lt;0.05), confirmándose además aislamiento por distancia (Mantel p 0.01; R20.06) y un alto nivel de endogamia a partir del déficit de heterocigotos en los loci evaluados (FIS0.45). Conclusiones. Se sugiere que la población de A. fúlica en el Valle del Cauca pudo tener más de un lugar de introducción o incluso más de una oleada de invasión. Además, el alto nivel de endogamia probablemente es el resultado de las actividades de control, las cuales eliminan individuos adultos de la población lo que conlleva al incremento de la deriva per se del efecto fundador.

Evaluation of genetic diversity and population structure of five Chinese indigenous donkey breeds using microsatellite markers

China had the largest population of raising donkeys in the world, however the number of Chinese indigenous donkey decreased dramatically due to the increase of agriculture mechanization in the last century. The species has still been important in China because of its edible and medical value, therefore the survey on its genetic diversity in China is necessary for its conservation and utilization. In this study, 15 microsatellite markers were used to evaluate genetic diversity and population structure of five Chinese indigenous donkey breeds. The mean values of expected heterozygosity, allelic richness, and total number of alleles for all the tested Chinese donkeys were 0.70, 6.04, and 6.28 respectively, suggesting that the genetic diversity of Chinese indigenous donkeys is rich. The Bayesian analysis and principal component analysis plot yielded the same clustering result, which revealed that Guanzhong donkey was the most differentiated breed in all detected samples, and Jinnan (JN) and Guangling (GL) were genetically closed together. Additionally, our results indicated that the heterozygote deficit was severe in two Chinese indigenous donkey breeds (GL and JN), and it warned us that animal conservation activities on this species should be considered carefully in near future.

Genetic characterization of residual Triatoma infestans populations from Brazil by microsatellite.

In spite of long-term efforts to eliminate Triatoma infestans (Klug 1834) from Brazil, residual foci still persist in the states of Bahia and Rio Grande do Sul. Data on the genetic variability and structuring of these populations are however lacking. Using nine microsatellite loci, we characterized one residual T. infestans population from Bahia and four from Rio Grande do Sul, and compared them with bugs originally from an older focus in São Paulo; 224 bugs were genotyped. The number of alleles per locus ranged from 5 to 11. Observed and expected heterozygosities per locus ranged, respectively, from 0 to 0.786 and from 0 to 0.764. Significant departures from Hardy-Weinberg equilibrium, mainly due to heterozygote deficits, were detected in all loci and in most populations. Global indices estimated by AMOVA were: Fis was 0.37; Fst was 0.28; and Fit was 0.55; overall indices with p = 0.00 indicated substantial differentiation. Inter-population Fst ranged from 0.118 to 0.562, suggesting strong genetic structuring and little to no gene flow among populations. Intra-population Fis ranged from 0.301 to 0.307. Inbreeding was apparent in all populations except that from Bahia-which might be either linked by gene flow to nearby unsampled populations or part of a relatively large local population. The overall pattern of strong genetic structuring among pyrethroid-susceptible residual T. infestans populations suggests that their persistence is probably due to operational control failures. Detection and elimination of such residual foci is technically feasible and must become a public health priority in Brazil.

Genetic characterization and founder effect analysis of recently introduced Salers cattle breed population

Salers are a native French breed used for beef and dairy production that has expanded to all the continents. The Salers breed was introduced to the north of Spain in 1985 with only 15 individuals from France and has successfully increased to over 20 000 animals. Although over time new animals have been imported from France for breeding, it is possible that the limiting number of founder animals could have resulted in a reduction of the genetic diversity found in Spanish Salers. Thus, the purpose of the present study has been to characterize the genetic diversity of Salers breed in Spain and evaluate a possible founder effect due to reduced number of the first reproducers. A total of 403 individuals from 12 Salers herds were analyzed using 12 microsatellite markers and compared with phylogenetically and geographically close related Blonde d’Aquitaine, Limousin and Charolais French breeds but also other 16 European breeds. Microsatellites in Salers were polymorphic, with a mean allelic richness of 5.129 and an expected heterozygosity of 0.621 across loci (0.576 to 0.736 among all breeds). Average observed heterozygosity was 0.618. All the loci fit the Hardy–Weinberg (HW) equilibrium except TGLA227 locus due to a significant deficit of heterozygotes in only one of the herds, probably attributable to a sampling effect. When all loci were combined, Salers inbreeding coefficient did not differ statistically from 0 (FIS=0.005), indicating not significant excess or deficit of heterozygotes (P=0.309). Based in allelic distribution, Salers revealed a frequency of 0.488 in BM2113-131 and 0.064 in BM2113-143 diagnostic alleles, which are specific to the African zebu. These zebu alleles are also found in some French breeds, supported by STR data previously postulated hypothesis of a migration route through Mediterranean route by which North African cattle may have left a genetic signature in southern Europe. Phylogenetic tree and population structure analyses could unambiguously differentiate Salers cattle from the other populations and 10% of the total genetic variability could be attributed to differences among breeds (mean RST=0.105; P<0.01). Mutation-drift equilibrium tests (sign test and Wilcoxon’s sign rank test) were in correspondence to the absence of founder effect when Bonferroni was applied. Gene diversity previously reported in French Salers was comparable with the observed in our population. Thus, high genetic diversity in Spanish Salers highlights the resources of this population, which looks toward future breeding and selection programs.

Genetic diversity assessment of an indigenous horse population of Greece

Highly endangered local breeds are considered important not only for the maintenance of their genetic diversity for future survival but also because they regarded as part of the cultural heritage of the local and national communities. Using pedigree data and an analysis of 18 microsatellite loci we investigated the genetic diversity of a private (commercial) indigenous Skyros horse population, reared in an insular region of North-Western of Greece. The overall average animal inbreeding value reached 24%. Concerning average inbreeding value over non founding animals, it was estimated to 0.013, while the corresponding value over inbred animals were 0.13.The mean number of alleles per locus amounted to 3.72, ranging between 1 and 7 alleles. The average observed heterozygosity was 0.57. Taking into account the inbreeding estimated index, an average heterozygote deficit (Fis) of -0.09 was noted (P&lt;0.05). Although the population maintained reasonable levels of genetic diversity, well studied inbreeding strategies should be implemented, in order to reduce the loss of genetic variability, to avoid extinction and further genetic drift of the population.

Characterization of sixteen microsatellite loci from the marine gastropod Monetaria caputdraconis (Gastropoda: Cypraeidae) by next generation sequencing

Easter Island possess a unique marine biodiversity. Monetaria caputdraconis is important among these species due to its cultural and economic importance for the islanders. For this reason, a total of 16 microsatellite loci were characterized for this species. The mean number of alleles per locus in the 76 studied individuals was 11.25 (2-20 alleles per locus) and the observed heterozygosity ranged from 0.08 to 0.88. While none of the loci exhibited significant linkage disequilibrium, 9 showed departures from Hardy-Weinberg equilibrium. The heterozygote deficit observed in M. caputdraconis has been described for other marine invertebrates with planktonic larval development.