Molecular DNA identity of the mouflon of Cyprus (Ovis orientalis ophion,Bovidae): Near Eastern origin and divergence from Western Mediterranean conspecific populations

The mouflon population of Cyprus (Ovis orientalis ophion) comprises historically preserved feral descendants of sheep domesticated during the Neolithic. We determined genetic identity of this taxon in order to elucidate its systematic placement and enforce its protection. We used 12 loci of microsatellite DNA to infer genetic relationships between the Cypriot mouflon and either long-time isolated (Corsica, Sardinia) or recently introduced (central Italy) European mouflons (O. o. musimon). We also sequenced the mitochondrial DNA (mtDNA) Cytochrome-b gene to infer the origin of the Cypriot mouflon including many National Centre for Biotechnology Information (NCBI) entries of European and Near Eastern conspecifics. Microsatellites disclosed net divergence between Western Mediterranean and Cypriot mouflon. The latter was included in the highly heterogeneous Near Eastern O. orientalis mtDNA group, Iran representing the most credited region as the source for its ancient introduction to Cyprus. Both international and national legislation protect the mouflon of Cyprus as a wild taxon (O. o. ophion). However, the IUCN Red List of Threatened Species and NCBI include the Cypriot mouflon as subspecies of its respective domestic species, the sheep (O. aries). Unfortunately, people charged with crime against protected mouflon may benefit from such taxonomic inconsistency between legislation and databases, as the latter can frustrate molecular DNA forensic outcomes. Until a definitive light can be shed on Near Eastern O. orientalis systematics, we suggest that the Cypriot mouflon should be unvaryingly referred to as O. o. ophion in order not to impair conservation in the country where it resides.     

Oxygen affinity of mouflon blood

Hemoglobin phenotypes of European mouflon and sheep were analyzed by isoelectric focusing; the results show that the sheep HbA migrated faster than that of other animals, while the mouflon HbA was more anodic than the sheep HbB. The oxygen dissociation curve of blood from mouflon is similar to that of sheep with HbA. The authors suggest that the mouflon should not be considered a direct ancestor of the Sardinian breed of sheep.     

The sequence and phylogenesis of the α-globin genes of Barbary sheep (Ammotragus lervia), goat (Capra hircus), European mouflon (Ovis aries musimon) and Cyprus mouflon (Ovis aries ophion)

In order to investigate the polymorphism of α-globin chain of hemoglobin amongst caprines, the linked ^Iα and ^IIα globin genes of Barbary sheep (Ammotragus lervia), goat (Capra hircus), European mouflon (Ovis aries musimon), and Cyprus mouflon (Ovis aries ophion) were completely sequenced, including the 5′ and 3′ untranslated regions. European and Cyprus mouflons, which do not show polymorphic α globin chains, had almost identical α globin genes, whereas Barbary sheep exhibit two different chains encoded by two nonallelic genes. Four different α genes were observed and sequenced in goat, validating previous observations of the existence of allelic and nonallelic polymorphism. As in other vertebrates, interchromosomal gene conversion appears to be responsible for such polymorphism. Evaluation of nucleotide sequences at the level of molecular evolution of the ^Iα-globin gene family in the caprine taxa suggests a closer relationship between the genus Ammotragus and Capra. Molecular clock estimates suggest sheep-mouflon, goat-aoudad, and ancestor-caprine divergences of 2.8, 5.7, and 7.1 MYBP, respectively.     

Genetic diversity in Iranian indigenous sheep vis-à-vis selected exogenous sheep breeds and wild mouflon

The heterogeneity of climate and different agro-ecological conditions in Iran have resulted in development of 27 indigenous sheep breeds. Wild Asiatic mouflon (Ovis orientalis) is believed to be the ancestor of Iranian sheep. Evaluation of genetic diversity and population structure within and among domestic breeds has important implications for animal breeding programs and genetic resources management. Based on 50K SNP genotype data, we studied the genetic diversity of five indigenous Iranian sheep breeds: Afshari (n = 37), Moghani (n = 34), Qezel (n = 35), Zel (n = 46) and Lori-Bakhtiari (n = 46), and Asiatic mouflon (n = 8) sampled from Iran. Furthermore, genetic diversity and the breed admixture of Iranian sheep were assessed on a larger geographic scale using a reference panel comprising: three indigenous Afghan breeds – Arabi (n = 15), Balouchi (n = 15) and Gadik (n = 15); three indigenous breeds from Turkey and Cyprus – Cyprus Fat Tail (n = 30), Karakas (n = 18) and Norduz (n = 20); and three commercial European breeds – Suffolk (n = 19), Comisana (n = 24) and Engadine Red Sheep (n = 24). The results revealed that the investigated breeds are divided into five genetically distinct clusters according to their geographic origin. Afshari was closest to the local mouflon population and showed signs of mouflon admixture. Qezel was identified as a hybrid sheep breed. Much evidence supported the Afghan breeds being identical. Inbreeding values, which were estimated based on ROHs, were highest for Suffolk (F_ROH = 0.0544) and lowest for Balouchi (F_ROH = 0.0078). In conclusion, analysis of selected breeds from neighboring countries along with Asiatic mouflon gave a deeper insight into the evolutionary history and origin of Iranian sheep with important implications for future breed management.     

Comparative aspects of biochemical polymorphism in the blood of Caprinae species and their hybrids

Biochemical variation at 14 blood loci was reviewed, and specific features compared experimentally in sheep Ovis aries, mouflon Ovis musimon, goat Capra hircus, aoudad Ammotragus lervia and in 2 stillborn aoudad × goat hybrids. Variation at 3 loci was also studied in dall sheep Ovis dalli, bighorn sheep Ovis canadensis and rocky mountain goat Oreamnos americanus. Haemoglobin C production in an anaemic Hb AB mouflon and in mouflon × sheep hybrids was examined. Mouflon differ from domestic sheep in that synthesis of both Hb β^AHb β^Bchains is switched off during Hb C production. The mouflon × sheep hybrids switched off one or both chains depending on whether they had inherited sheep or mouflon Hb β chain genes. In general aoudad showed a closer affinity to goats than to sheep.     

Molecular analysis of wild and domestic sheep questions current nomenclature and provides evidence for domestication from two different subspecies

Complete mitochondrial DNA (mtDNA) control regions (CR) were sequenced and analysed in order to investigate wild sheep taxonomy and the origin of domestic sheep (Ovis aries). The dataset for phylogenetic analyses includes 63 unique CR sequences from wild sheep of the mouflon (O. musimon, O. orientalis), urial (O. vignei), argali (O. ammon) and bighorn (O. canadensis) groups, and from domestic sheep of Asia, Europe and New Zealand. Domestic sheep occurred in two clearly separated branches with mouflon (O. musimon) mixed into one of the domestic sheep clusters. Genetic distances and molecular datings based on O. canadensis CR and mtDNA protein-coding sequences provide strong evidence for domestications from two mouflon subspecies. Other wild sheep sequences are in two additional well-separated branches. Ovis ammon collium and O. ammon nigrimontana are joined with a specimen from the transkaspian Ust-Urt plateau currently named O. vignei arkal. Ovis ammon ammon, O. ammon darwini and O. vignei bochariensis represent a separate clade and the earliest divergence from the mouflon group. Therefore, O. musimon, O. vignei bochariensis and Ust-Urt sheep are not members of a 'moufloniform' or O. orientalis species, but belong to different clades. Furthermore, Ust-Urt sheep could be a hybrid population or an O. ammon subspecies closely related to O. ammon nigrimontana.     

“Conservation cloning” of vulnerable Esfahan mouflon (Ovis orientalis isphahanica): in vitro and in vivo studies

Among the wide range of bio-conservational strategies envisaged, recent accomplishments in the field of interspecies somatic cell nuclear transfer (iSCNT) hold considerable promise due to its unique potential to decelerate or prevent rapid loss of animal genetic resources, and even to revive extinct species. Accordingly, this study was carried out to investigate if in vitro matured and enucleated oocytes of domestic sheep could be used for interspecies conservation cloning of Esfahan mouflon (Ovis orientalis isphahanica), a vulnerable species classified by the International Union for Conservation of Nature. Cryo-banked fibroblasts of a mouflon (derived from a genome resource bank) and a domestic sheep (prepared during a recent study) were cultured in vitro and used for karyotyping. Prior to SCNT, fibroblast donor cells were serum starved for 5 days. Using the zona-free SCNT technique, in vitro matured and enucleated domestic sheep oocytes were reconstituted with nuclei donor cells of mouflon and domestic sheep, and their competencies for in vitro development to the blastocyst stage were compared. The cloned mouflon blastocysts were then surgically transferred into the uterus of the synchronized domestic sheep. Karyotype analysis confirmed that fibroblasts of the Esfahan mouflon had the correct number of diploid chromosomes (2n = 54). Evaluation of 907 activated reconstructs [Esfahan mouflon (n = 667), domestic sheep (n = 240)] revealed no significant difference in the term of blastocyst development (7.6 ± 0.5% vs. 9.3 ± 0.5%, respectively). After the transfer of 12 cloned Esfahan mouflon blastocysts to five domestic sheep recipients, two (40.0%) pregnancies were established in which both (100%) were sustained until caesarean section (days 147 and 150 of pregnancy, respectively) and culminated in the live births of cloned Esfahan mouflon lambs. However, the newborns did not survive and died soon after birth. Karyotype and genetic analyses confirmed that both clones had correct diploid chromosome number (2n = 54), and were genetically identical to each other in addition to their original cell donor. This study highlighted the importance of “conservation cloning” using closely related abundant alternate species.

     

Re-sequencing regions of the ovine Y chromosome in domestic and wild sheep reveals novel paternal haplotypes

The male-specific region of the ovine Y chromosome (MSY) remains poorly characterized, yet sequence variants from this region have the potential to reveal the wild progenitor of domestic sheep or examples of domestic and wild paternal introgression. The 5' promoter region of the sex-determining gene SRY was re-sequenced using a subset of wild sheep including bighorn ( Ovis canadensis ), thinhorn ( Ovis dalli spp.), urial ( Ovis vignei ), argali ( Ovis ammon ), mouflon ( Ovis musimon ) and domestic sheep ( Ovis aries ). Seven novel SNPs ( oY 2– oY 8) were revealed; these were polymorphic between but not within species. Re-sequencing and fragment analysis was applied to the MSY microsatellite SRYM18 . It contains a complex compound repeat structure and sequencing of three novel size fragments revealed that a pentanucleotide element remained fixed, whilst a dinucleotide element displayed variability within species. Comparison of the sequence between species revealed that urial and argali sheep grouped more closely to the mouflon and domestic breeds than the pachyceriforms (bighorn and thinhorn). SNP and microsatellite data were combined to define six previously undetected haplotypes. Analysis revealed the mouflon as the only species to share a haplotype with domestic sheep, consistent with its status as a feral domesticate that has undergone male-mediated exchange with domestic animals. A comparison of the remaining wild species and domestic sheep revealed that O. aries is free from signatures of wild sheep introgression.     

Hematology and serum biochemistry of European mouflon (<Emphasis Type="Italic">Ovis orientalis musimon</Emphasis>) in Croatia

The aim of the present study was to determine the reference intervals for the most commonly used hematological and biochemical parameters of European mouflon from a closed hunting ground in the eastern part of the Republic of Croatia. Blood samples were collected from 39 live, physically restrained, clinically normal European mouflon, as well as from 50 domestic sheep. The distribution of values within each parameter was determined and statistical differences in values between sexes were also determined. For each sample, 14 hematological and 18 biochemical parameters were analyzed. Hematology and biochemistry values of the European mouflon were also compared with the values of domestic sheep. In further studies, the established values might be useful for the health assessment of mouflon.     

Comparison of biochemical polymorphisms in mouflon and sheep: isoelectric differences in haemoglobins and quantitative variation of mouflon haemopexin

1. Of ten protein systems studied in mouflon (Ovis musimon), five were polymorphic (Tf, Hpx, EsA, X-protein, Cat). Electrophoretic mobilities of mouflon proteins did not differ from those of sheep. 2. Mouflon haemoglobin B and sheep haemoglobin B differed in isoelectric focusing. 3. Haemopexin levels in mouflon were determined by rocket immunoelectrophoresis. A trimodal distribution was apparent, with no haemopexin, low and high levels of the protein. The results are indicative of genetic control of haemopexin levels, one of the alleles being inactive (Hpx0).     

Influence of age on the relationship between annual changes in horn growth rate and prolactin secretion in the European mouflon (Ovis gmelini musimon)

Annual variations in the growth of horns, and their correlation with seasonal changes of testicular size, and prolactin (PRL) and melatonin secretion were monitored in six pubertal mouflon rams living in their original latitude (40 degrees N). Mouflons born and maintained under captive conditions were classified in two age classes: sub-adult (2 years; n=3) and adult (> or =3 years; n=3). The rate of horn growth was greater (P <0.001) in sub-adult than in adult mouflon rams. Horn growth was influenced by season in both adult and sub-adult mouflons (P <0.05) with largest monthly growth occurring in spring and summer. Seasonal variations of plasma PRL concentrations were correlated with horn growth in adult, but not in sub-adult mouflon rams. The rate of horn growth was inversely correlated with testicular size (r=-0.5, P=0.07). Seasonal changes in the amplitude of the daily melatonin rhythm in solstices and equinoxes were observed, which were not correlated with variations in the rate of horn growth. These results provide support for a possible role of PRL in the control of growth of horns in the adult mouflon.     

Reproductive potential of domestic Ovis aries for preservation of threatened Ovis orientalis isphahanica: in vitro and in vivo studies

Although the potential use of reproductive biotechnology for safeguarding of endangered wildlife species is undoubted, initial evaluation of the genetic and reproductive relationship between the endangered mammals and those closely related species is indispensable. Isfahan mouflon Ovis orientalis isphahanica is now considered as a threatened species by International Union for the Conservation of Nature. Therefore, little is known about the biology of this species. This study was carried out to investigate the possible reproductive potential of domestic sheep for ex situ conservation of the Isfahan mouflon. Somatic cell cultures were taken from ear biopsies of the wild and domestic sheep and were used for karyotype analysis. Semen samples were collected by electroejaculator from the wild and domestic rams. The spermatological characteristics of the collected semen samples were determined and used for both cryopreservation and cross-insemination of the synchronized wild and domestic female sheep. To establish a cryobank for the threatened species biomaterials, freezed samples of the somatic cells and semen were transferred to a cryotank. The result suggested that Isfahan mouflon has conserved its chromosomal integrity as previously observed and contains the same chromosomal number as the domestic sheep (2n = 54). The semen samples of both species revealed similar cryoviability (>35% gross motility postthawing). Cross-insemination of both species resulted in successful pregnancy. It was suggested that domestic sheep possesses the required biological characteristics to be considered for safeguarding of the Isfahan mouflon.     

In vivo and in vitro fertilizing capacity of cryopreserved European mouflon [Ovis gmelini musimon] spermatozoa used to restore genetically rare and isolated populations

European mouflon sheep are an endangered species of ovidae residing primarily in the mountenous habitat of the islands of Sardinia and Corsica. The purpose of this study was to assess the fertilizing capacity of cryopreserved European mouflon spermatozoa after AI in synchronized mouflon and domestic ewes and after IVF in in vitro matured mouflon and domestic ewe oocytes collected by OPU technique. Domestic ram (Ovis aries) spermatozoa served as control. Semen was collected by artificial vagina from three mouflons and three domestic rams during the breeding season and was cryopreserved. At thawing, no significant differences in sperm viability were found between the wild and the domestic species (53.1 +/- 4.6% versus 56.0 +/- 4.7%) whereas the percentage of acrosome-intact sperm was lower in mouflon (55.5 +/- 4.6%) than in ram semen (62.7 +/- 3.1%; P < 0.05). Lambing rate did not differ between synchronized mouflon and domestic ewes (5/11 versus 8/12) after 150 and 156 days of pregnancy, respectively. After two OPU sessions, 87 and 132 oocytes were collected from three hyperstimulated mouflon and three domestic ewes. Cryopreserved/thawed semen was inseminated with an endoscope into the uterus of corresponding species during the non-breeding season. The oocytes were matured and fertilized in vitro; 61/73 mouflon and 81/101 domestic ewe oocytes were found to be fertilized. From these, we obtained 6/61 and 17/81 blastocysts. After vitrification and thawing, the hatching rate showed no significant difference between mouflon and sheep blastocysts (4/6 versus 14/17). In conclusion, our data showed that cryopreserved mouflon spermatozoa can be successfully used to carry out a genuine and complete program of genetic restoration in small and isolated groups of European mouflons.     

Haemoglobin phenotypes of the wild European mouflon sheep living on the island of Sardinia

Haemoglobin (Hb) phenotypes have been studied in 100 wild European mouflons living on the island of Sardinia by means of isoelectric focusing (pH 6.7-7.7 range) of the native tetramers, acid-urea-Triton gel-electrophoresis, and reversed-phase HPLC of globin chains. The result indicates the presence of two beta-globin alleles one of which, corresponding to the beta B, being the most common (f = 0.94). None were carriers of the earlier described Hb A. The new Hb was provisionally named Hb M. Severely anaemic mouflons were able to synthesize Hb C at expense of the Hb B alone, thus suggesting structural and physiological homologies between mouflon beta B and sheep beta A globin genes, and between the newly observed beta M allele and the beta B of the domestic Sardinian sheep.     

Sheep haemopexin: immunological cross-reactivity with other vertebrate sera and evidence for the absence of haemopexin in some mouflon

A monospecific antiserum to sheep haemopexin was produced in rabbits. By using this antiserum, as well as absorbed antisera to sheep and mouflon serum proteins, it was proved that some mouflon sera lack haemopexin. In immunodiffusion, when using the monospecific antiserum, immunoprecipitates were present only in species' belonging to suborder Ruminantia. None of the other mammalian, nor any of the avian, reptilian, amphibian and fish species tested, showed reaction.     

A Hu sheep genome with the first ovine Y chromosome reveal introgression history after sheep domestication

The Y chromosome plays key roles in male fertility and reflects the evolutionary history of paternal lineages. Here, we present a de novo genome assembly of the Hu sheep with the first draft assembly of ovine Y chromosome(o MSY), using nanopore sequencing and Hi-C technologies. The o MSY that we generated spans 10.6 Mb from which 775 Y-SNPs were identified by applying a large panel of whole genome sequences from worldwide sheep and wild Iranian mouflons. Three major paternal lineages(HY1a, HY1b and HY2) were defined across domestic sheep, of which HY2 was newly detected. Surprisingly, HY2 forms a monophyletic clade with the Iranian mouflons and is highly divergent from both HY1a and HY1b. Demographic analysis of Y chromosomes, mitochondrial and nuclear genomes confirmed that HY2 and the maternal counterpart of lineage C represented a distinct wild mouflon population in Iran that diverge from the direct ancestor of domestic sheep, the wild mouflons in Southeastern Anatolia. Our results suggest that wild Iranian mouflons had introgressed into domestic sheep and thereby introduced this Iranian mouflon specific lineage carrying HY2 to both East Asian and Africa sheep populations.     

Kinetics of the ontogenic and reversible hemoglobin switching in the mouflon (Ovis musimon) and sheep x mouflon hybrid.

1. Hemoglobin (Hb) switching in the perinatal life of wild mouflon (Ovis musimon) was characterized by the replacement of Hb F by 60% levels of Hb C, and subsequently of Hb C by Hb B. 2. The recently discovered Hb M variant was not replaced by Hb C; thus, Hb BM heterozygote newborns synthesized 30% Hb C at the expense of Hb B. 3. Hybrid B mouflon x B sheep synthesized only 5% Hb C at birth but were able to produce 30% Hb C in adult life following induced anemia. 4. Adult BB and BM mouflons, after the same extent of induced anemia, synthesized HB C levels similar to those produced at birth. The results indicate a mouflon beta-globin gene cluster arrangement similar to those of sheep and goat, the beta C gene having an intermediate expression. Results also suggest a selective disadvantage in hybrid animals.     

Seasonal cycles in the blood plasma concentration of FSH, inhibin and testosterone, and testicular size in rams of wild, feral and domesticated breeds of sheep

Seasonal cycles in testicular activity in rams were monitored in groups of wild (mouflon), feral (Soay) and domesticated breeds of sheep (Shetland, Blackface, Herdwick, Norfolk, Wiltshire, Portland and Merino) living outdoors near Edinburgh (56 degrees N). The changes in the blood plasma concentrations of FSH, inhibin and testosterone, and the diameter of the testis were measured every half calendar month from 1 to 3 years of age. There were significant differences between breeds in the magnitude and timing of the seasonal reproductive cycle. In the mouflon rams, the seasonal changes were very pronounced with a 6-15-fold increase in the plasma concentrations of FSH, inhibin and testosterone from summer to autumn, and a late peak in testicular diameter in October. In the Soay rams and most of the domesticated breeds, the seasonal increase in the reproductive hormones occurred 1-2 months earlier with the peak in testicular size in September or October. In the two southern breeds (Portland and Merino), the early onset of testicular activity was more extreme with the seasonal maximum in August. In cross-bred rams, produced by mating Soay ewes (highly seasonal breed) with Portland or Merino rams (less seasonal breeds), there was a seasonal reproductive cycle that was intermediate compared to that of the parents. A comparison between all 11 breeds showed a significant correlation between the timing of the seasonal cycle in plasma FSH concentration and testicular diameter (time of peak FSH vs testis, r = 0.95). The overall results in the rams are consistent with a primary role of FSH in dictating the seasonal cycle in testicular size and the secretion of inhibin. The earlier seasonal onset in the testicular cycle in the southern breeds of domesticated sheep, and the differences from the wild type, are taken to represent the effects of genetic selection for a longer mating season.     

Correlation with changes in horns and pelage, but not reproduction, of seasonal cycles in the secretion of prolactin in rams of wild, feral and domesticated breeds of sheep

Seasonal cycles were monitored in groups of wild (mouflon), feral (Soay) and domesticated breeds of sheep (Shetland, Blackface, Herdwick, Norfolk, Wiltshire, Portland, Merino, Soay x Portland and Soay x Merino) living outdoors near Edinburgh (56 degrees N). Changes in the blood plasma concentrations of prolactin and FSH, and growth of the horns and pelage were measured every half calendar month from 1 to 3 years of age. In all breeds there was a clearly defined seasonal cycle in the plasma concentration of prolactin with an 18-66-fold increase in mean values from the nadir in November and December to the peak in May and June. The seasonal increase in prolactin was closely correlated with the seasonal increase in the growth of the horns, both within and between breeds (e.g. time of peak prolactin vs horn growth for 11 breeds, R = 0.62, P less than 0.05). In the mouflon, Soay and some of the domesticated breeds of sheep (Wiltshire, Herdwick and Shetland), the seasonal increase in prolactin was also temporally correlated with the resurgence of growth of the pelage in spring and a conspicuous moult. In the other breeds developed to produce fine wool (e.g. Norfolk, Portland and Merino), there was no clear seasonal change in the pelage and growth continued throughout the year. Comparison between breeds indicated that continuous growth of the pelage was associated with higher plasma prolactin concentrations in winter. The times of the seasonal changes in plasma concentrations of prolactin were not significantly correlated with the corresponding changes in the plasma concentrations of FSH. The overall results are consistent with a role for prolactin related to the growth of the horns and pelage rather than the seasonal cycle in reproduction. The differences between the wild-type and the domesticated breeds in the pelage represent the effect of selective breeding to produce a long fine fleece which has involved changes in both the seasonal pattern of prolactin secretion and the growth characteristics of the hair fibres.     

Sheep mitochondrial DNA variation in European, Caucasian, and Central Asian areas

Three distinct mitochondrial maternal lineages (haplotype Groups A, B, and C) have been found in the domestic sheep. Group B has been observed primarily in European domestic sheep. The European mouflon carries this haplotype group. This could suggest that European mouflon was independently domesticated in Europe, although archaeological evidence supports sheep domestication in the central part of the Fertile Crescent. To investigate this question, we sequenced a highly variable segment of mitochondrial DNA (mtDNA) in 406 unrelated animals from 48 breeds or local varieties. They originated from a wide area spanning northern Europe and the Balkans to the Altay Mountains in south Siberia. The sample included a representative cross-section of sheep breeds from areas close to the postulated Near Eastern domestication center and breeds from more distant northern areas. Four (A, B, C, and D) highly diverged sheep lineages were observed in Caucasus, 3 (A, B and C) in Central Asia, and 2 (A and B) in the eastern fringe of Europe, which included the area north and west of the Black Sea and the Ural Mountains. Only one example of Group D was detected. The other haplotype groups demonstrated signs of population expansion. Sequence variation within the lineages implied Group A to have expanded first. This group was the most frequent type only in Caucasian and Central Asian breeds. Expansion of Group C appeared most recently. The expansion of Group B involving Caucasian sheep took place at nearly the same time as the expansion of Group A. Group B expansion for the eastern European area started approximately 3,000 years after the earliest inferred expansion. An independent European domestication of sheep is unlikely. The distribution of Group A variation as well as other results are compatible with the Near East being the domestication site. Groups C and D may have been introgressed later into a domestic stock, but larger samples are needed to infer their geographical origin. The results suggest that some mitochondrial lineages arrived in northern Europe from the Near East across Russia.