Abstract Black lion tamarin (BLT) monkeys ( Leontopithecus chrysopygus ) have suffered a severe reduction in their natural range and are consequently critically endangered. Because allozyme data showed very low levels of variation, it was not clear if these monkeys had much genetic diversity. We designed microsatellite primers for BLTs, and from them we identified nine polymorphic loci, seven of which were tested on golden lion tamarins (GLTs) ( Leontopithecus rosalia ). All of the seven polymorphic loci and two other monomorphic BLT loci were polymorphic in GLTs. The microsatellite markers identified here are directly applicable to ongoing lion tamarin population and conservation genetics studies.
Abstract: Canine biological specimens are often part of the physical evidence from crime scenes. Until now, there have been no validated canine‐specific forensic reagent kits available. A multiplex genotyping system, comprising 18 short tandem repeats (STRs) and a sex‐linked zinc finger locus for gender determination, was developed for generating population genetic data assessing the weight of canine forensic DNA profiles. Allele frequencies were estimated for 236 pedigreed and 431 mixed breed dogs residing in the U.S. Average random match probability is 1 in 2 × 10 33 using the regional database and 1 in 4 × 10 39 using the breed dataset. Each pedigreed population was genetically distinct and could be differentiated from the mixed breed dog population but genetic variation was not significantly correlated with geographic transition. Results herein support the use of the allele frequency data with the canine STR multiplex for conveying the significance of identity testing for forensic casework, parentage testing, and breed assignments.
Rhesus macaques are the most common nonhuman primate model organism used in biomedical research. Their increasingly frequent use as subjects in studies involving transplantation requires that blood and other tissue antigens of donors and recipients be compatible. We report here an easy and rapid multiplex polymerase chain reaction (PCR) to determine the ABO blood group phenotypes of rhesus macaques that can be performed with only small amounts of DNA. We phenotyped 78 individuals and found this species to exhibit the A, B and AB phenotypes in frequencies that vary by geographic region. The probability of randomly pairing rhesus macaque donors and recipients that exhibit major ABO phenotype incompatibility is approximately 0.35 and 0.45 for Indian and Chinese rhesus macaques, respectively.
Regional populations of rhesus and long-tailed macaques exhibit fundamental differences in mitochondrial DNA, short tandem repeat and single nucleotide polymorphism variation between mainland and insular Southeast Asian populations. Some studies have revealed genetic admixture between these species due to natural hybridization and human-assisted intercrosses. A quantitative real-time PCR (qPCR) assay was developed to efficiently determine the species of origin of a macaque biological sample, and to quantify the species-specific template DNA. Prior knowledge of species identity and DNA concentrations are crucial for maintaining cost-effective methods and accurate DNA analysis. DNA from 109 regionally representative rhesus and long-tailed macaques was qPCR amplified to determine the species and template quantities. Of the 19 Vietnamese long-tailed macaques, 3 samples were discovered to be hybrids.
Among social vertebrates, immigrants may incur a substantial fitness cost when they attempt to join a new group. Dispersers could reduce that cost, or increase their probability of mating via coalition formation, by immigrating into groups containing first- or second-degree relatives. We here examine whether dispersing males tend to move into groups containing fathers or brothers in gray-cheeked mangabeys (Lophocebus albigena) in Kibale National Park, Uganda. We sampled blood from 21 subadult and adult male mangabeys in 7 social groups and genotyped them at 17 microsatellite loci. Twelve genotyped males dispersed to groups containing other genotyped adult males during the study; in only 1 case did the group contain a probable male relative. Contrary to the prediction that dispersing males would follow kin, relatively few adult male dyads were likely first- or second-degree relatives; opportunities for kin-biased dispersal by mangabeys appear to be rare. During 4 yr of observation, adult brothers shared a group only once, and for only 6 wk. Mean relatedness among adult males sharing a group was lower than that among males in different groups. Randomization tests indicate that closely related males share groups no more often than expected by chance, although these tests had limited power. We suggest that the demographic conditions that allow kin-biased dispersal to evolve do not occur in mangabeys, may be unusual among primates, and are worth further attention.
Despite the popularity of dogs in US households, canine DNA evidence remains largely untapped in forensic investigations partially because of the absence of well-defined forensic short tandem repeats (STRs), lack of standardized and validated PCR protocols, STR reagent kits, and poorly developed nomenclature. A nomenclature system was established based on internationally recognized recommendations for human forensic STRs for a recently developed canine STR reagent kit. Representative alleles were sequenced from each of the 18 STRs and the sex-typing marker included in the kit. This study also reflects on the impact of point mutations, insertions, and deletions within and outside the STR core repeat structures. An understanding of the STRs' sequence and repeat structures will enable development of a robust and reliable allele nomenclature and improve the accuracy and precision of allele fragment sizing in canine forensic profiling. The expected allele sizes have been calculated, and their repeat stuctures defined based on sequence information.
Rhesus macaques (Macaca mulatta) are the primate most used for biomedical research, but phenotypic differences between Indian-origin and Chinese rhesus macaques have encouraged genetic methods for identifying genetic differences between these two populations. The completion of the rhesus genome has led to the identification of many single nucleotide polymorphisms (SNPs) in this species. These single nucleotide polymorphisms have many advantages over the short tandem repeat (STR) loci currently used to assay genetic variation. However, the number of currently identified polymorphisms is too small for whole genome analysis or studies of quantitative trait loci. To that end, we tested a combination of methods to identify large numbers of high-confidence SNPs, and screen those with high minor allele frequencies (MAF).By testing our previously reported single nucleotide polymorphisms, we identified a subset of high-confidence, high-MAF polymorphisms. Resequencing revealed a large number of regionally specific SNPs not identified through a single pyrosequencing run. By resequencing a pooled sample of four individuals, we reliably identified loci with a MAF of at least 12.5%. Finally, we found that when applied to a larger, geographically variable sample of rhesus, a large proportion of our loci were variable in both populations, and very few loci were ancestry informative. Despite this fact, the SNP loci were more effective at discriminating Indian and Chinese rhesus than STR loci.Pyrosequencing and pooled resequencing are viable methods for the identification of high-MAF SNP loci in rhesus macaques. These SNP loci are appropriate for screening both the inter- and intra-population genetic variation.
Abstract Background Fullbred Chinese and Indian rhesus macaques represent genetically distinct populations. The California National Primate Research Center introduced Chinese founders into its Indian‐derived rhesus colony in response to the 1978 Indian embargo on exportation of animals for research and the concern that loss of genetic variation in the closed colony would hamper research efforts. The resulting hybrid rhesus now number well over a thousand animals and represent a growing proportion of the animals in the colony. Methods We characterized the population genetic structure of the hybrid colony and compared it with that of their pure Indian and Chinese progenitors. Results The hybrid population contains higher genetic diversity and linkage disequilibrium than their full Indian progenitors and represents a resource with unique research applications. Conclusions The genetic diversity of the hybrids indicates that the strategy to introduce novel genes into the colony by hybridizing Chinese founders and their hybrid offspring with Indian‐derived animals was successful.
Abstract Background While rates of gene flow between rhesus and longtail macaque populations near their hybrid zone in Indochina have been quantified elsewhere, this study demonstrates that the inter‐specific introgression is not limited to the Indochinese hybrid zone but is more geographically widespread. Methods Twelve rhesus and longtail macaque populations were analyzed using single nucleotide polymorphic (SNP) loci. Results There is evidence for inter‐specific admixture between Chinese rhesus and mainland longtails, with implications for genetic diversity both in the Chinese super‐SPF population at the California National Primate Research Center and in other primate facilities. Eastern Chinese rhesus appeared more highly derived than western Chinese rhesus, and allele sharing between longtails and Chinese rhesus was not random with regard to geographic distance, but no significant nuclear genetic differences between eastern and western Chinese rhesus were detected among the 245 genic SNPs assayed. Conclusion The implications of this inter‐specific admixture for the use of Chinese rhesus and mainland longtail in biomedical research should be considered.