Bovine Microsatellite Markers Research Articles

Molekularna filogenija i genetička raznolikost domaćih jakova (Bos grunniens) u Pakistanu na temelju mitohondrijskih i mikrosatelitskih markera

The complete Cytchrome b gene and partial mtDNA control region were sequenced for the Pakistani domestic yak (Bos grunniens) within the Bovidae family. A total of 300 samples were genotyped using 27 bovine microsatellite markers from the Gilgit-Baltistan and Skardu regions of Pakistan. We identified a total of 35 mutations and 9 haplotypes based on D-loop sequences, with a haplotype and nucleotide diversity of 0.9640±0.051 and 0.02172±0.00224, respectively. For the Cyt b gene, a total of 23 variable sites and six different haplotypes were observed with 0.885±0.067 haplotype and 0.00989±0.003 nucleotide diversity. Phylogenetic analysis of D-loop and Cyt b gene suggested that domestic yak sequences cluster into two highly divergent maternal lineages (lineages I and II), while three haplogroups A, C, and D were identified of the six previously known haplogroups. Haplogroups A and C were dominant and widely distributed among all investigated yak samples. All microsatellites were polymorphic and a total of 138 alleles were observed, with average polymorphic information content (PIC) of 0.56 indicating their effectiveness. The average heterozygosity was observed at 0.6071 with allele diversity of 5.1111 and gene diversity of 0.4830. The implications of these findings can be applied for yak conservation.

Genetic Diversity Analysis of Five Egyptian Buffalo Populations Using Microsatellite Markers

For assessing the genetic diversity and genetic characterization of five Egyptian buffalo populations a total of 12 microsatellite markers were used. The total number of buffaloes sampled was 80, collected at random from five farms in five different governorates; Cairo, Kafr El-Sheikh, Shebeen El-Kom, Menoufia, and Beni Suef. The genetic parameters (allelic diversity, allelic frequencies, observed heterozygosity, unbiased expected heterozygosity, and polymorphic information content) were calculated using three different programs. All used microsatellites were polymorphic and ranged from four alleles (Loci; CSSM029, CSSM036, CSSM038, CSSM043, CSSM046, and ILSTS005) to nine alleles (Loci; BM1818 and CSSM047) with a total of 64 alleles in the whole population. Allelic richness for the whole population ranged between 3.297 (in locus CSSM029) and 6.806 (in locus CSSM047) with overall mean 4.574. Within populations, Kafr El-Sheikh population had the highest average of allelic richness (4.384). This indicates the potential of this population to adapt with environmental changes in future compared with other populations. BMC1013, BM1818, CSSM019, and CSSM047 showed the highest allelic richness. PIC estimates were high and ranged between 0.65 (in locus CSSM029) and 0.92 (in locus CSSM022) with an average of 0.82. Values of Ho were lower than values of HNb for all populations, which denoting depression of heterozygotes in these populations and may be attributable to existence of null alleles and inbreeding. This study as well proves the usefulness of heterologous bovine microsatellite markers in evaluation of the genetic variability in Egyptian buffalo populations due to high polymorphism, informativeness of these markers which can be used to develop future breeding strategies and conservation decisions on our indigenous breed.

Genetic characterization and assessment of diversity in Pandharpuri buffalo breed of India using heterologous microsatellite markers

The present study was aimed at genetic characterization and diversity analysis of Pandharpuri buffalo population using the Food and Agriculture Organization (FAO) recommended bovine microsatellite markers. Genomic DNA was isolated from blood samples of 50 unrelated animals and a total of 23 microsatellite loci were amplified using polymerase chain reaction. Among 23 recommended microsatellite markers, 14 markers (BM2113, BM1818, CSSM66, HEL13, INRA037, ILSTS05, HAUT27, INRA023, INRA035, HEL5, ETH3, NRA063, MM12 and ETH10) were found to be highly polymorphic in Pandharpuri population. The amplified products were run on polyacrylamide gel electrophoresis (PAGE) apparatus along with a ladder; subsequently, the allele typing was done based on silver staining of the gel. The effective and observed number of alleles, heterozygosity (expected and unbiased) estimates and polymorphic information content (PIC) levels were estimated for each locus. A total of 87 alleles were secured for 14 polymorphic loci studied giving an overall average of 6.21 alleles per locus. The number of alleles ranged from 2 (INRA063) to 9 (BM1818 and HEL13). The mean effective number of alleles across all polymorphic loci was found to be 4.28. The overall mean expected heterozygosity and unbiased expected heterozygosity values were 0.77 and 0.76, ranging from 0.50 (INRA063) to 0.88 (BM1818) and 0.50 (INRA063) to 0.88 (BM1818), respectively. The average PIC estimate across all polymorphic loci was 0.73 ranging from 0.373 (INRA063) to 0.864 (BM1818). In the present study, the characterization and diversity estimates are reported for Pandharpuri population. It was found to maintain optimum diversity based on 14 polymorphic microsatellite markers.

Microsatellite-based Genetic Diversity and Mutation-Drift Equilibrium in Dharwadi Buffalo (Bubalus bubalis) of India

Genetic diversity was assessed in a buffalo population (Dharwadi) of Karnataka by utilizing 25 heterologous bovine microsatellite markers. Genotypic status of individuals at each locus was identified by automated DNA sequencer, and allelic data were analyzed for genetic diversity parameters. Observed number of alleles varied between 5 and 19 with 13.12 ± 0.80 alleles per locus. High level of heterozygosity (0.63) indicated plenty of existing genetic diversity in this buffalo population. Within-population inbreeding estimate (FIS) was significantly positive (0.186) and 88% of the investigated loci contributed toward the homozygote excess. Accordingly, significant deviation from Hardy–Weinberg equilibrium was observed at 24 of 25 analyzed loci. The population did not suffer reduction in effective population size in the last few generations. Assessment of Dharwadi buffalo population for mutation-drift equilibrium did not reveal significant heterozygosity excess under all the models of microsatellite evolution as per Sign test. No shift was recorded in the frequency distribution of alleles, and a normal L-shaped curve indicated absence of any recent genetic bottleneck. The study highlighted sufficient genetic variability within Dharwadi buffalo population that can be utilized in combination with phenotype and production information for registration as a distinct breed of Indian buffalo.

Cattle microsatellite markers successfully established diversity status of Arunachali yak (only registered yak breed of India)

Yak diversity of the country has remained predominantly unexplored for a long time. Among the 169 registered livestock breeds of India, the sole representation from yak genetic resources is the Arunachali yak. This study for the first time investigated genetic diversity status of Arunachali yak using 26 bovine microsatellite markers. All the markers recommended for cattle except one (ILSTS05) amplified with yak genome. Allelic genotype pattern overlapped between yak and cattle across 25 microsatellite loci and a total of 233 alleles were detected in yak. The number of observed alleles across loci ranged from 3–16 with an average of 9.32±0.70. Observed heterozygosity (0.552±0.04) was less than the expected heterozygosity (0.648±0.035) pointing towards heterozygote deficiency in the population. In addition, positive value of FIS index (0.143±0.043) suggested considerable inbreeding. There was no indication of a recent bottleneck event in this population based on heterozygosity excess tests as well as mode-shift analysis. In summary, bovine microsatellite markers proved to be a valuable tool for characterization of Indian yak population. Arunachali yak represents an interesting gene pool with moderate level of diversity. Inbreeding in population calls for sincere efforts to formulate breeding policy so that this precious germplasm is conserved with substantial genetic diversity.

Analysis of microsatellite markers in a Cuban water buffalo breed

The aim of this Regional Research Communication was to validate a panel of 30 microsatellite markers recommended by FAO/ISAG for studies of biodiversity in cattle to improve the characterisation of Cuban buffalo populations. The water buffalo (Bubalus bubalis) is an economically important livestock species. Therefore, research focused on the study of the genetic relationships among water buffalo populations is useful to support conservation decisions and to design breeding schemes. Twenty-eight of the 30 tested regions were amplified, one of which (ETH10) turned out to be monomorphic. A total of 143 alleles were observed in the Cuban water buffalo population. The average number of alleles per locus was 5·04. The number of alleles per polymorphic locus ranged from two (INRA 63 and MM12) to nine (ETH185). The observed and expected heterozygosity ranged from 0·108 (HAUT24) to 0·851 (CSSM66) and 0·104 (MM12) to 0·829(INRA32), respectively. The polymorphic information content (PIC) ranged from 0·097 (MM12) to 0·806 (INRA32), and the overall value for these markers was 0·482. Within the population, inbreeding estimates (F IS) was positive in 14 of the 30 loci analysed. This study thus highlights the usefulness of heterologous bovine microsatellite markers to assess the genetic variability in Cuban water buffalo breeds. Furthermore, the results can be utilised for future breeding strategies and conservation.

Microsatellite based genetic diversity among the three water buffalo (<i>Bubalus bubalis</i>) populations in Turkey

Abstract. In this study, twenty microsatellite loci were used to define genetic diversity among 56 water buffalo samples. Their somatic tissues (the skin and cartilage tissues from ears) and DNAs were deposited in Turkish Gene Banks. Samples of healthy animals were collected from three different geographic regions: Northern Turkey, North-Western Turkey and Eastern Thrace. Three (loci CSSM57, ETH3) to ten (locus CSSM47) different alleles were identified per micro-satellite locus in a total of 103 alleles. PIC values for the micro-satellite loci analysed ranged from 0.14 (CSSM32) to 0.82 (CSSM47) with a mean of 0.4945. In all of the populations for each of the loci, the observed heterozygosities (HO) were greater than the expected heterozygosities (HE), indicating that populations suffered from bottleneck. HE per population ranged between 0.5359 in the Black Sea Region and 0.5208 in the Aegean-South Marmara Region. Within the population, inbreeding estimates (FIS) was positive in only four of the 20 loci analysed. Individuals of the different geographic populations did not cluster on the neighbour joining tree which was constructed on the basis of allele sharing distances. Population differentiation was further visualized by Factorial Correspondence Analysis and determined by the pairwise estimations of fixation index (FST) and Nei’s standard genetic distance (Da). The results revealed that populations have inertia (as depicted by Factorial Correspondence Analysis), they are differentiated significantly but little (by pairwise FST values) and the least genetic distance is between Black Sea Region and Thrace Region. Comparative studies indicated that the genetic diversity of water buffalo harboured in the Gene Banks of Turkey is at the lower end of the diversity spectrum. This study thus highlights the usefulness of heterologous bovine microsatellite markers to assess the genetic variability in Anatolian water buffalo breeds. Furthermore, the results can be utilized for future breeding strategies and conservation.

소 Y 염색체-특이 MS 마커를 이용한 한국재래소의 유전적 특징

소 Y 염색체-특이 MS 마커를 이용한 한국재래소의 유전적 특징

Association mapping of genetic risk factors for chronic wasting disease in wild deer

Chronic wasting disease (CWD) is a fatal transmissible spongiform encephalopathy affecting North American cervids. We assessed the feasibility of association mapping CWD genetic risk factors in wild white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) using a panel of bovine microsatellite markers from three homologous deer linkage groups predicted to contain candidate genes. These markers had a low cross-species amplification rate (27.9%) and showed weak linkage disequilibrium (<1 cM). Markers near the prion protein and the neurofibromin 1 (NF1) genes were suggestively associated with CWD status in white-tailed deer (P = 0.006) and mule deer (P = 0.02), respectively. This is the first time an association between the NF1 region and CWD has been reported.

Differentiation of four indian aboriginal cattle populations revealed by SIR markers

Cattle are the most important livestock in India and play a pivotal role in agrarian economy. There are 34 recognized breeds of cattle and number of unexplored lesser known populations. The present study is a contribution towards determining genetic variation and understanding the relationship among four lesser known populations. A total of 194 unrelated DNA samples from three cattle populations of Orissa (Binjharpuri, Ghumsuri, Motu) and Hill cattle of Kumaun (Kumauni) were collected from respective breeding tracts. Genotyping was done with 23 bovine microsatellite markers as suggested by International Society for Animal Genetics (ISAG) and FAO (DAD-IS) on automated sequencer. The average observed heterozygosity in the four populations lie within the narrow range of 0.623 +/- 0.04 in Binjharpuri to 0.664 +/- 0.03 in Kumauni. Mean estimates of observed and expected heterozygosity over all loci and breeds were 0.651 +/- 0.02 and 0.720 +/- 0.01, respectively. In the overall population, the homozygote excess (F(IT)) of 0.132 +/- 0.03, was partly due to the genetic differentiation among breeds (F(ST) = 0.044 +/- 0.01) and, to a larger extent, to a significant homozygote excess within breeds (F(IS) = 0.094 +/- 0.03). The phylogenetic reconstruction from a UPGMA clustering based on Nei's Standard genetic distance yielded a tree with Binjharpuri and Ghumsuri on a single node and Motu and Kumauni on separate nodes. The most probable clustering detected by STRUCTURE in population was three. Binjharpuri and Ghumsuri animals were assigned to one cluster with high proportion of membership.

Microsatellite analysis of Kangayam cattle (Bos indicus) of Tamilnadu

Assessment of genetic variability in Kangayam breed of cattle in Tamilnadu, South India was carried out using 25 bovine microsatellite markers. The mean number of alleles was 4.04 ± 0.09 with a range of 2 to 6 and the allele size ranged from 94 to 300 bp. The frequency distribution of alleles in the breed was from 0.0104 to 0.9167. The estimated heterozygosity was 0.6183 ± 0.01 and the PIC was 0.5628 ± 0.03. The overall mean within-population inbreeding estimate (FIS) value (- 0.084) suggested excess of heterozygotes in the population. In addition, higher PIC value indicated the scope for maintaining variation in the population and strategies to take meaningful conservation.

Genetic diversity and bottleneck analysis of Nagpuri buffalo breed of India based on microsatellite data

In this study, 25 heterologous bovine microsatellite markers have been used for the assessment of genetic diversity in Nagpuri buffalo, an important breed of Central India. For this, 48 DNA samples of unrelated individuals of Nagpuri buffalo were PCR amplified and microsatellite alleles were resolved in 6% denaturing, silver stained Urea-PAGE gel. Genotypic status of individuals at each locus was identified manually and data analysis carried out using POPGENE software. Observed number of alleles varied from 2 (ILSTS073 locus) to 8 (HEL13 & ILSTS058 loci) with a mean of 5.24 alleles per locus. Moderate level of heterozygosity (0.45) indicated sufficient genetic diversity existing in this buffalo population. PIC values for the microsatellite loci analysed, ranged from 0.10 (ILSTS019 locus) to 0.81 (ILSTS058 locus) with a mean of 0.53. No shift in the frequency distribution of alleles and a normal L-shaped curve indicated non-existence of any bottleneck in Nagpuri. The study thus highlights the usefulness of heterologous bovine microsatellite markers to assess the genetic variability in buffalo breeds as well. Also various diversity indices suggest sufficient genetic variability within Nagpuri buffalo that can be utilized as initial guidelines for future breeding strategies and conservation.

Characterization of Banni buffalo of Western India

SummaryThe Banni buffaloes distributed in the Kachchh region of Gujarat state in western India are medium to large in body size with a compact body and typical coiled horns. Mean body length, heart girth and height at withers estimated during the survey were 153.7±0.4 cm, 205.5±0.6 cm and 136.7±0.2 cm, respectively. Data on 397 adult milking buffaloes from Banni area based on interviews with farmers, revealed the mean age at first calving to be 39.7±0.4 months, a mean service period of 66.4±1.3 days, a mean lactation length of 293.3±1.5 days and a mean peak yield of 15.7±0.1 litres. Genetic diversity analysis of Banni buffaloes using a set of 15 heterologus bovine microsatellite markers revealed a high degree of allelic polymorphism with a total of 81 alleles and a mean of 5.4. The observed heterozygosity was found to be moderate with a mean of 0.506 and ranged from 0.125 (ILSTS 045) to 0.795 (ILSTS 008). The mean F value (0.181) across 15 microsatellite loci was significantly positive indicating heterozygote deficiency in the population. The test for Hardy-Weinberg equilibrium revealed seven of the 15 microsatellite loci analyzed showing significant deviations.

52 EFFECT OF TRICHOSTATIN A ON DEVELOPMENTAL POTENTIAL OF INTER-SPECIES CLONED GAUR (BOS GAURUS) EMBRYOS

This study was carried out to investigate the effect of trichostatin A (TSA) treatment on interspecies cloned gaur (Bos gaurus) embryos development and implantation rate after transfer to bovine (Bos taurus) recipients. The bovine (Bos taurus) enucleated oocytes were used as recipient cytoplasm for male and female gaur fibroblasts. After electrical fusion, oocytes were separated into two groups, TSA treatment and control. For the TSA group, the oocytes were placed in EmCare (ICPbio, Ltd., Auckland, New Zealand) holding medium + 50 nm TSA for 1 h. The fused oocytes were activated by 7% ethanol + 50 nm TSA for 5 min at room temperature and 10 μg mL–1 cycloheximide + 1.25 μg mL–1 cytochalasin D + 50 nm TSA at 38.5°C under 5% CO2 in air for 5 h. Then the embryos were cultured in mSOFaa medium + 3 mg mL–1 bovine serum albumin (BSA) + 50 nm TSA up to 10 h. After 10 h, the reconstructed embryos were transferred to embryo culture medium without TSA and culture for 2 days at 38.5°C under 5% CO2, 5% O2, 90% N2. The control embryos were cultured with the same culture system without TSA supplementation. Eight-cell stage embryos were selected and co-cultured with bovine oviductal epithelial cells in culture medium at 38.5°C under 5% CO2 in air for 5 days. Half volume of the culture medium was replaced daily. Two blastocysts at days 7 or 8 derived from male fibroblasts of treated and non-treated TSA were non-surgically transferred to each synchronized estrous bovine recipients. The statistical analysis was done by ANOVA and the comparison of means by Duncan’s Multiple Range Test (DMRT). The development to blastocyst stage was not different among male and female, treated and non-treated TSA embryos which range between 34.8 to 39.3%. The pregnancy rate at 40 days after recipients received cloned embryos derived from male fibroblasts treated v. non-treated TSA was 11% (2/18) v. 10% (1/10) (Table 1). One recipient which received a non-treated embryo gave birth by C-section on March 4, 2008. The male gaur calf died from respiratory problem at 12 h after birth. Eight bovine microsatellite markers analysis confirmed that the newborn gaur was derived from the donor gaur fibroblast. In this study, TSA has no effect on pre-implantation cloned gaur embryos development either derived from male or female gaur fibroblasts. Cloned gaur calves could be produced by interspecies cloning using bovine oocytes as recipient cytoplasm. Table 1.Pregnancy and birth rates after transferred cloned gaur embryos derived from male fibroblasts to recipients This study was supported by National Center for Genetic Engineering and Biotechnology (BIOTEC) and Suranaree University of Technology.

Genetic Diversity in River Buffalo (Bubalus bubalis) Breeds of Central India using Heterologous Bovine Microsatellite Markers

Mishra, B.P., Kataria, R.S., Bulandi, S.S., Kumar, V. and Mukesh, M. 2008. Genetic diversity in river buffalo (Bubalus bubalis) breeds of central India using heterologous bovine microsatellite markers. J. Appl. Anim. Res., 33: 159–163. A panel of 25 bovine specific heterologous microsatellite markers was employed for evaluating both within and between breed genetic variability estimates in Pandharpuri and Nagpuri buffaloes, two prominent breeds of Central India. A total of 148 alleles were detected across the two breeds with mean number of 5.92 alleles. The mean allelic diversity and heterozygosity reflected the existence of relatively higher genetic variability in Nagpuri buffalo. The F-statistics estimates were significantly different from zero (P<0.05) with F (F IT) = 0.349 ± 0.051, f(F IS) = 0.254 ± 0.039, θ(FST) = 0.126 ± 0.042. Most of the genetic variations correspond to differences among individuals (87.4%). Various genetic differentiation estimates indicated moderate differentiation between Nagpuri and Pandharpuri buffaloes. Individual assignment and inter-individual allele sharing estimates also substantiated the presence of discrete genetic structure in both the buffalo breeds from Central India.

Genomic conservation of cattle microsatellite loci in wild gaur (Bos gaurus) and current genetic status of this species in Vietnam

BackgroundThe wild gaur (Bos gaurus) is an endangered wild cattle species. In Vietnam, the total number of wild gaurs is estimated at a maximum of 500 individuals. Inbreeding and genetic drift are current relevant threats to this small population size. Therefore, information about the genetic status of the Vietnamese wild gaur population is essential to develop strategies for conservation and effective long-term management for this species. In the present study, we performed cross-species amplification of 130 bovine microsatellite markers, in order to evaluate the applicability and conservation of cattle microsatellite loci in the wild gaur genome. The genetic diversity of Vietnamese wild gaur was also investigated, based on data collected from the 117 successfully amplified loci.ResultsOne hundred-thirty cattle microsatellite markers were tested on a panel of 11 animals. Efficient amplifications were observed for 117 markers (90%) with a total of 264 alleles, and of these, 68 (58.1%) gave polymorphic band patterns. The number of alleles per locus among the polymorphic markers ranged from two to six. Thirteen loci (BM1314, BM2304, BM6017, BMC2228, BMS332, BMS911, CSSM023, ETH123, HAUT14, HEL11, HEL5, ILSTS005 and INRA189) distributed on nine different cattle chromosomes failed to amplify wild gaur genomic DNA. Three cattle Y-chromosome specific microsatellite markers (INRA124, INRA126 and BM861) were also highly specific in wild gaur, only displaying an amplification product in the males. Genotype data collected from the 117 successfully amplified microsatellites were used to assess the genetic diversity of this species in Vietnam. Polymorphic Information Content (PIC) values varied between 0.083 and 0.767 with a mean of 0.252 while observed heterozygosities (Ho) ranged from 0.091 to 0.909 (mean of 0.269). Nei's unbiased mean heterozygosity and the mean allele number across loci were 0.298 and 2.2, respectively.ConclusionExtensive conservation of cattle microsatellite loci in the wild gaur genome, as shown by our results, indicated a high applicability of bovine microsatellites for genetic characterization and population genetic studies of this species. Moreover, the low genetic diversity observed in Vietnamese wild gaur further underlines the necessity of specific strategies and appropriate management plans to preserve this endangered species from extinction.

Microsatellite Marker Based Characterization of Genetic Diversity in Kankrej Cattle

Sodhi, M, Mukesh, M., Prakash, B., Mishra, B.P, Sobti, R.C., Singh, K.P. and Ahlawat, S.P.S. 2007. Microsatellite marker based characterization of genetic diversity in Kankrej cattle. J. Appl. Anim. Res, 31: 153–158. This study contributes to the knowledge of genetic structure I diversity of Kankrej cattle (a dual purpose breed) from Gujarat state of India. Molecular data generated using bovine specific microsatellite markers was utilized to assess the existing genetic diversity. The mean number of observed and effective alleles was 8.2 and 4.2, respectively. The average observed heterozygosity values (0.694) compared to the average expected heterozygosity values (0.717) did not show significant differences in the selected population (P>0.05), suggesting random mating in Kankrej. The allele diversity and gene diversity values imply a substantial amount of genetic variability in Kankrej cattle. Population inbreeding estimates (FIs = −0.013) indicated the absence of inbreeding (P<0.05) in this breed.

The effect of activation treatments on the development of reconstructed bovine oocytes

The purpose of this study was to investigate the effect of different activation treatments on the development of IVM-derived and cloned bovine embryos. The effect of oocyte age (20 h versus 24 h after IVM) on the blastocyst rate was also investigated. No differences in the percentage of blastocyst development were observed between the oocytes matured for 20 and 24 h (15% versus 27%, p > 0.05). Reconstructed oocytes activated 4 h after fusion (fusion before activation, FBA) had a higher blastocyst rate than those oocytes activated immediately after electrofusion (fusion and activation simultaneously, FAS) (26% versus 5%, p < 0.01). Blastocyst rates were significantly greater ( p < 0.01) for the reconstructed oocytes activated by calcium ionophore (A23187) combined with 6-dimethylaminopurine (6-DMAP) (51.6%) than for those activated with cycloheximide (CHX) plus cytochalasin B (CB) treatment (1 h, 8.2%; 5 h, 14.3%). However, the blastocyst rates were similar among reconstructed oocytes activated by electric pulses and A23187 (30.5% versus 42.2%) or by A23187 and ionomycin (36.7% versus 33.3%) combined with 6-DMAP, respectively. Blastocysts that developed from reconstructed oocytes activated by A23187 and 6-DMAP resulted in three pregnancies (3/9) and one live birth from 18 embryos transferred to recipient cows. Genotypic analysis of six bovine microsatellite markers by polymerase chain reaction confirmed that the cloned calf was genetically identical to the nuclear donor. In conclusion, reconstructed oocytes that derived from oocytes exposed to activation treatment 4 h after electrofusion are more likely to develop to the blastocyst stage. The best treatment to activate reconstructed bovine oocytes in this study was A23187 combined with 6-DMAP.

A radiation hybrid map of sheep chromosome 23 based on ovine BAC‐end sequences

More than 375,000 BAC-end sequences (BES) of the CHORI-243 ovine BAC library have been deposited in public databases. blastn searches with these BES against HSA18 revealed 1806 unique and significant hits. We used blastn-anchored BES for an in silico prediction of gene content and chromosome assignment of comparatively mapped ovine BAC clones. Ovine BES were selected at approximately 1.3-Mb intervals of HSA18 and incorporated into a human-sheep comparative map. An ovine 5000-rad whole-genome radiation hybrid panel (USUoRH5000) was typed with 70 markers, all of which mapped to OAR23. The resulting OAR23 RH map included 43 markers derived from BES with high and unique BLAST hits to the sequence of the orthologous HSA18, nine EST-derived markers, 16 microsatellite markers taken from the ovine linkage map and two bovine microsatellite markers. Six new microsatellite markers derived from the 43 mapped BES and the two bovine microsatellite markers were linkage-mapped using the International Mapping Flock (IMF). Thirteen additional microsatellite markers were derived from other ovine BES with high and unique BLAST hits to the sequence of the orthologous HSA18 and also positioned on the ovine linkage map but not incorporated into the OAR23 RH map. This resulted in 24 markers in common and in the same order between the RH and linkage maps. Eight of the BES-derived markers were mapped using fluorescent in situ hybridization (FISH), to thereby align the RH and cytogenetic maps. Comparison of the ovine chromosome 23 RH map with the HSA18 map identified and localized three major breakpoints between HSA18 and OAR23. The positions of these breakpoints were equivalent to those previously shown for syntenic BTA24 and HSA18. This study presents evidence for the usefulness of ovine BES when constructing a high-resolution comprehensive map for a single sheep chromosome. The comparative analysis confirms and refines knowledge about chromosomal conservation and rearrangements between sheep, cattle and human. The constructed RH map demonstrates the resolution and utility of the newly constructed ovine RH panel.

Application of bovine microsatellite markers for genetic diversity analysis of European bison (Bison bonasus)

In this study, the cross-amplification of a commercial multiplex set of 11 cattle (Bos taurus) microsatellites was tested on a panel of 35 European bison (Bison bonasus) individuals. After polymerase chain reaction optimization, all loci cross-amplified successfully in investigated bisons. Number of alleles and observed and expected heterozygosity per locus are in the range of 2-4, 0.086-0.629 and 0.288-0.621 respectively. The availability of a heterologous set of multiplexed microsatellite markers derived from cattle opens an avenue for collecting profound genetic data for efficient conservation management strategies of the European bison.