Molekulargenetische Untersuchungen beim Einsiedler-Pferd

In this study it was investigated whether the "Einsiedler" warmblood horse, a historically old horse population from central Switzerland (Abbey of Einsiedeln), is distinguishable from micellaneous horse breeds, using molecular genetic techniques. The breeding history of Einsiedler horses is characterised by systematic line breeding through the dams. Therefore, two Einsiedler dam lines (N = 28), going back to the middle of the 19th century according to pedigree entries, were the focus of the survey. Random samples of diverse warmblood horse populations, but also samples from more distinct types of horse breeds, served as comparison populations (N = 52). Variation in the mitochondrial genome appeared to be only partially informative to demarcate the studied horses, as horses of distinct breeds may share identical mtDNA sequence fragments. Both dam lines revealed haplotypes commonly found in Iberian horse breeds. This is to take as an indication on the genetic origin of Einsiedler horses. Furthermore, the Klima dam line held a homologous mtDNA sequence fragment with E. ferus przewalskii. Therefore, this seems to be a phylogenetically old haplotype. The analysis of microsatellite loci revealed that horses from the two Einsiedler dam lines were in fact distinguishable from more distinct types of horses, but not from closely related European warmblood horse breeds and English thoroughbred.

[Polychondritis: a new disease in Swiss Braunvieh?]

Over the last 10 years Swiss Braunvieh cattle with malformations of the pinnae have repeatedly been reported. Endoscopy revealed a shortened and thickened epiglottis and malformations of the arytenoid cartilage in some of these animals. In most cases the elastic cartilage was replaced by fibrocartilage and hyaline cartilage. The direct cause and pathogenesis of the malformations could not be determined.

Clinical and molecular characterization of a re-established line of sheep exhibiting hemophilia A

BACKGROUND

Large animal models that accurately mimic human hemophilia A (HA) are in great demand for developing and testing novel therapies to treat HA.

OBJECTIVES

To re-establish a line of sheep exhibiting a spontaneous bleeding disorder closely mimicking severe human HA, fully characterize their clinical presentation, and define the molecular basis for disease.

PATIENTS/METHODS

Sequential reproductive manipulations were performed with cryopreserved semen from a deceased affected ram. The resultant animals were examined for hematologic parameters, clinical symptoms, and responsiveness to human FVIII (hFVIII). The full coding region of sheep FVIII mRNA was sequenced to identify the genetic lesion.

RESULTS AND CONCLUSIONS

The combined reproductive technologies yielded 36 carriers and 8 affected animals. The latter had almost non-existent levels of FVIII:C and extremely prolonged aPTT, with otherwise normal hematologic parameters. These animals exhibited bleeding from the umbilical cord, prolonged tail and nail cuticle bleeding time, and multiple episodes of severe spontaneous bleeding, including hemarthroses, muscle hematomas and hematuria, all of which responded to hFVIII. Inhibitors of hFVIII were detected in four treated animals, further establishing the preclinical value of this model. Sequencing identified a premature stop codon and frame-shift in exon 14, providing a molecular explanation for HA. Given the decades of experience using sheep to study both normal physiology and a wide array of diseases and the high homology between human and sheep FVIII, this new model will enable a better understanding of HA and facilitate the development and testing of novel treatments that can directly translate to HA patients.

Tentative chromosomal localization of the bovine major histocompatibility complex by in situ hybridization

A genetic region, most likely the major histocompatibility complex, was assigned to bands q13-23 of cattle chromosome 23 by in situ hybridization using a cloned DNA sequence of a class I gene of the pig major histocompatibility complex.

Porcine malignant hyperthermia carrier detection and chromosomal assignment using a linked probe

In pigs, the gene for glucosephosphate isomerase (GPI) is linked to the halothane (HAL) gene which is responsible for malignant hyperthermia (MH). A single copy DNA probe, designated GPI8R, has been isolated from a pig genomic library using a porcine GPI cDNA probe. This probe detects, as was the case for the cDNA probe, a five allele polymorphism in SacI and PvuII digested pig DNA. Family studies show that this polymorphism is linked to the HAL locus and hence can be used in carrier detection. In situ hybridization with GPI8R assigned the GPI locus to bands p12-q22 of chromosome 6. We conclude that the HAL linkage group resides on chromosome 6.

Recombination rates and gene order for some serum alpha-protease inhibitors and immunoglobulin heavy-chain allotypes in pigs

Linkage analysis between the genes coding for immunoglobulin heavy-chain allotypes and variants of some serum alpha-protease inhibitors produced lod scores above the significance limit of 3. The maximum likelihood estimate of the recombination fraction (theta) ranged from 0.15 to 0.20. Since this is the second report on this linkage group in pigs, the linkage is confirmed. Data from appropriate matings are consistent with a gene order of Pi1-Po1A-(Po1B)-Pi2-Igh1.

Veterinary cytogenetics: past and perspective

Cytogenetics was conceived in the late 1800s and nurtured through the early 1900s by discoveries pointing to the chromosomal basis of inheritance. The relevance of chromosomes to human health and disease was realized more than half a century later when improvements in techniques facilitated unequivocal chromosome delineation. Veterinary cytogenetics has benefited from the information generated in human cytogenetics which, in turn, owes its theoretical and technical advancement to data gathered from plants, insects and laboratory mammals. The scope of this science has moved from the structure and number of chromosomes to molecular cytogenetics for use in research or for diagnostic and prognostic purposes including comparative genomic hybridization arrays, single nucleotide polymorphism array-based karyotyping and automated systems for counting the results of standard FISH preparations. Even though the counterparts to a variety of human diseases and disorders are seen in domestic animals, clinical applications of veterinary cytogenetics will be less well exploited mainly because of the cost-driven nature of demand on diagnosis and treatment which often out-weigh emotional and sentimental attachments. An area where the potential of veterinary cytogenetics will be fully exploited is reproduction since an inherited aberration that impacts on reproductive efficiency can compromise the success achieved over the years in animal breeding. It is gratifying to note that such aberrations can now be tracked and tackled using sophisticated cytogenetic tools already commercially available for RNA expression analysis, chromatin immunoprecipitation, or comparative genomic hybridization using custom-made microarray platforms that allow the construction of microarrays that match veterinary cytogenetic needs, be it for research or for clinical applications. Judging from the technical refinements already accomplished in veterinary cytogenetics since the 1960s, it is clear that the importance of the achievements to date are bound to be matched or out-weighed by what awaits to be accomplished in the not-too-far future.

145 REESTABLISHMENT OF AN EXTINCT STRAIN OF SHEEP UTILIZING ASSISTED REPRODUCTIVE TECHNOLOGIES

The objective of this study was to reestablish an extinct strain of sheep that exhibits spontaneous X-linked factor VIII deficiency closely mimicking human hemophilia A. Twenty female carriers of the trait, produced in a previous study (Bormann et al. 2006 Reprod. Fertil. Dev. 18, 201–202), were backcrossed using 3 straws of semen from their affected sire using either IVF or multiple ovulation embryo transfer (MOET). Eleven oocyte donors were synchronized with CIDRs (15 days) and superovulated with a declining dose of FSH (204 mg) twice daily for 3.5 days. Nine MOET donors were synchronized using CIDRs (14 days), superovulated with a declining dose of FSH (184 mg) BID for 3 days with pregnant mare serum gonadotropin (PMSG; 200 IU) given with the final dose of FSH, and given 1000 IU of hCG 12 h post-CIDR removal. Recipient ewes were synchronized using sponges (Ovakron, HeriotAgvet, Rowville, Victoria, Australia) containing 30 mg of flugestone acetate (14 days) and given PMSG (400 IU) at sponge removal, followed by 1000 IU of hCG 12 h post-sponge removal. Oocytes were collected via follicular aspiration during midventral laparotomy and matured as previously reported. Semen for IVF was prepared by centrifugation on a Percoll gradient. Oocytes and sperm were incubated in mTALP with 20% estrus sheep serum (modified from Bavister et al. 1977 Bio. Reprod. 16, 228–237) for 20 h, then vortexed to remove cumulus cells, and cultured in G1.3 medium (Vitrolife, Englewood, CO) with BSA until transfer. Embryos were surgically transferred into oviducts of recipients 24 to 48 h following IVF. The 9 MOET donors were surgically inseminated at the uterotubal junction with approximately 1–2.0 � 106 spermatazoa. Oviducts of eight of these ewes were flushed 48 h post-insemination with warm M199 containing Hanks salts, 25 mm HEPES, 10% FBS, and 0.5 µg mL–1 gentamicin. MOET embryos were surgically transferred to synchronized recipients within 5 h. One MOET donor was not flushed due to poor response and did not produce an offspring. Utilizing 140 ova, IVF produced 54 embryos for an embryo/oocyte rate of 38.6%. All IVF embryos were transferred into 15 recipients resulting in 3 lambs for a lamb/embryo rate of 5.5%. The MOET donors produced 38 embryos and 13 apparently unfertilized ova, generating an embryo/oocyte rate of 74.5%. MOET embryos were transferred into 21 synchronized recipients. MOET produced 16 lambs for a lamb/embryo rate of 42.1%. Co-transfer of 1 IVF and 1 MOET embryo into a single recipient produced one offspring. Utilizing multiple reproductive technologies over a two-year period, 8 hemophilic offspring (7 females and 1 male), 6 carrier females, and 6 unaffected males were produced. This strain of sheep will be used to produce affected offspring for stem cell-based therapies.

Analysis and mapping of CACNB4, CHRNA1, KCNJ3, SCN2A and SPG4, physiological candidate genes for porcine congenital progressive ataxia and spastic paresis

The cause of porcine congenital progressive ataxia and spastic paresis (CPA) is unknown. This severe neuropathy manifests shortly after birth and is lethal. The disease is inherited as a single autosomal recessive allele, designated cpa. In a previous study, we demonstrated close linkage of cpa to microsatellite SW902 on porcine chromosome 3 (SSC3), which corresponds syntenically to human chromosome 2. This latter chromosome contains ion channel genes (Ca(2+), K(+) and Na(+)), a cholinergic receptor gene and the spastin (SPG4) gene, which cause human epilepsy and ataxia when mutated. We mapped porcine CACNB4, KCNJ3, SCN2A and CHRNA1 to SSC15 and SPG4 to SSC3 with the INRA-Minnesota porcine radiation hybrid panel (IMpRH) and we sequenced the entire open reading frames of CACNB4 and SPG4 without finding any differences between healthy and affected piglets. An anti-epileptic drug treatment with ethosuximide did not change the severity of the disease, and pigs with CPA did not exhibit the corticospinal tract axonal degeneration found in humans suffering from hereditary spastic paraplegia, which is associated with mutations in SPG4. For all these reasons, the hypothesis that CACNB4, CHRNA1, KCNJ3, SCN2A or SPG4 are identical with the CPA gene was rejected.

Radiation hybrid mapping of 18 positional and physiological candidate genes for arthrogryposis multiplex congenita on porcine chromosome 5

We report the chromosomal assignment of 18 porcine genes to human homologues using the INRA-Minnesota swine radiation hybrid panel (IMpRH). These genes (CACNA1C, COL2A1, CPNE8, C3F, C12ORF4, DDX11, GDF11, HOXC8, KCNA1, MDS028, TMEM106C, NR4A1, PHB2, PRICKLE1, Q6ZUQ4, SCN8A, TUBA8 and USP18) are located on porcine chromosome 5 (SSC5) and represent positional and functional candidates for arthrogryposis multiplex congenita (AMC), which maps to SSC5. CPNE8, PRICKLE1, Q6ZUQ4 and TUBA8 were mapped to the interval for pig AMC between microsatellites SW152 and SW904. Three SNPs in TUBA8 co-segregated with the AMC phenotype in 230 pigs of our research population without recombination and could be used as a genetic marker test for AMC. In addition, we provide evidence that a small chromosomal region of HSA22q11.2 evolutionarily corresponds to SSC5q12-q22 (and contains the human homologues of porcine SW152, Q6ZUQ4, TUBA8 and USP18), while the regions flanking HSA22q11.2 on SSC5 correspond to HSA12p13 and HSA12q12. We identified seven distinct chromosomal blocks, further supporting extensive rearrangements between genes on HSA12 and HSA22 in the AMC region on SSC5.

187 RE-ESTABLISHMENT OF AN EXTINCT STRAIN OF SHEEP FROM A LIMITED SUPPLY OF FROZEN SEMEN

The objective of this study was to restore a line of sheep that exhibits spontaneous X-linked factor VIII deficiency closely mimicking human hemophilia A. Six straws of frozen semen from an affected Alpine White male were obtained from Switzerland. In the first experiment the straw of semen thawed was of poor quality. Two ewes were synchronized for use as embryo donors (MOET) by means of CIDRs for 14 days and superovulated with declining doses of FSH (184 mg) twice daily for 3 days. PMSG (200 IU) was given with the final dose of FSH and 1000 IU of hCG 12 h post-CIDR removal. The ewes were surgically inseminated 24 h later. Oviducts were flushed 48 h post-insemination producing 13 unfertilized ova (UFO). Spermatozoa were used for intracytoplasmic sperm injection (ICSI) utilizing oocytes collected from superstimulated ewes by laporatomy. These ewes were synchronized with CIDRs (15 days) and superovulated with a declining dose of FSH (204 mg) twice daily for 3.5 days. Utilizing 236 oocytes, ICSI produced 189 embryos, an 80% embryo/oocyte rate. Embryos were transferred surgically to the oviducts of 17 synchronized recipients. Recipients were synchronized using sponges (Ovakron; Heriot Agvet, Rowville, Victoria, Australia) containing 30 mg of flugestone acetate (14 days) and given PMSG (400 IU) at sponge removal, followed by 1000 IU of hCG 12 h post-sponge removal. Eleven recipients produced 17 lambs for a lamb/embryo rate of 8.9%. The straw of semen utilized for the second experiment was of higher quality. Three ewes were superstimulated for use as MOET donors, as above, with increased doses of FSH (228 mg) and PMSG (500 IU). Donors were surgically inseminated and oviductal flushes were performed 40 h post-insemination, yielding 19 UFO and 12 embryos for an embryo/oocyte rate of 38.7%. Embryos were transferred to four recipients, synchronized as above with an increased dose of PMSG (600 IU). These MOET recipients produced nine lambs for a lamb/embryo rate of 75%. Semen was used to produce embryos via in vitro fertilization (IVF) using oocytes collected from superstimulated ewes (as above with an increase of FSH to 252 mg). IVF produced 91 embryos from 247 oocytes for an embryo/oocyte rate of 36.8%. Embryos were transferred to 20 recipients 24 to 48 h post-fertilization. Seven recipients maintained pregnancy and produced 10 lambs with a lamb/embryo rate of 11%. ICSI was also utilized, producing 54 embryos from 98 oocytes, an embryo/oocyte rate of 55.1%. Embryos were transferred to eight recipients; none maintained pregnancy. Through the use of multiple reproductive technologies, 36 lambs (22 carriers) were produced from two straws of semen. Carriers will be bred back to their sire in a similar program to produce affected lambs. The authors would like to acknowledge J. Liu and M. Ridha for their contributions. This work was supported by NIH Grant HL073737-12.

Identification and characterization of novel peroxisome proliferator-activated receptor-gamma (PPAR-gamma) transcriptional variants in pig and human

The peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is a member of the steroid/thyroid/retinoid receptor superfamily, and is primarily expressed in fat tissue. To date, two major PPAR-gamma isoforms have been identified in pig, PPAR-gamma1 and PPAR-gamma2. Porcine PPAR-gamma1a consists of two leader exons, designated A1 and A2, followed by six exons containing the open reading frame. Here, we report the isolation and characterization of three novel PPAR-gamma1 transcripts. PPAR-gamma1b is derived from exon A1, with exon A2 spliced out. PPAR-gamma1c and PPAR-gamma1d are derived from the new exon, A', containing exon A2 (gamma1c) or without exon A2 (gamma1d). Based on PCR analysis of PAC clones that included sequences from the 5'-untranslated region of the PPAR-gamma gene, the new A' exon is located between the known exons A1 and A2. We also isolated the human homologue to exon A', as well as the two new PPAR-gamma1c and -gamma1d splice variants, from human adipose tissue. Studies of the expression of porcine PPAR-gamma by real time reverse transcription-polymerase chain reaction analysis show that transcripts derived from exon A1 were not expressed at significantly different levels in visceral fat (lamina subserosa) or subcutaneous fat (back fat, inner and outer layer). In contrast, exon A'-derived transcripts were expressed at progressively higher levels in the inner and outer layers of subcutaneous fat than in visceral fat. The same expression pattern was also observed for PPAR-gamma2. We hypothesize that there are three promoters, which differentially regulate PPAR-gamma1 and PPAR-gamma2 gene expression, depending on the specific localization of the fat tissue.

Bovine spinal muscular atrophy: AFG3L2 is not a positional candidate gene

Bovine spinal muscular atrophy (BSMA) is a neurodegenerative disorder, which is widespread in Brown Swiss cattle. Main symptoms of the disease are muscular atrophy and recumbency. Affected calves die within few days or weeks. BSMA seems to be inherited as a recessive trait and the disease allele appears to have a common origin. In this study, a pedigree with 30 affected BSMA calves was used to genetically localize the BSMA locus. Linkage analysis was performed between microsatellite markers of seven chromosomes, where the homologous genes of human neurodegenerative disorders are located according to comparative mapping data, and the disease genotype. BSMA was mapped to chromosome 24 confirming the recently published localization (Medugorac et al. 2003). The candidate gene AFG3L2 was physically mapped to chromosome 24q24 using fluorescence in situ hybridization. Due to their different localizations AFG3L2 is not a positional candidate for BSMA. An informative marker localized on the telomeric side of the BSMA locus would be beneficial for marker-assisted selection as well as searching for the causative gene. However, finding a marker distal to BSMA locus is difficult because of its position at the end of the chromosome.

Phylogenetic analysis and species allocation of individual equids using microsatellite data

The taxonomic status of all equid species is not completely unravelled. This is of practical relevance for conservation initiatives of endangered, fragmented equid populations, such as the Asiatic wild asses (in particular Equus hemionus onager and E. hemionus kulan). In this study, a marker panel consisting of 31 microsatellite loci was used to assess species demarcation and phylogeny, as well as allocation of individuals (n = 120) to specific populations of origin (n = 11). Phylogenetic analysis revealed coalescence times comparable with those previously published from fossil records and mtDNA data. Using Bayesian approaches, it was possible to distinguish between the studied equids, although individual assignment levels varied. The observed results support the maintenance of separate captive conservation herds for E. hemionus onager and E. hemionus kulan. The first molecular genetic results for E. hemionus luteus remained contradictory, as they unexpectedly indicated a closer genetic relationship between E. hemionus luteus and E. kiang holderi compared with the other hemiones.

Inheritance of the F4ab, F4ac and F4ad E. coli receptors in swine and examination of four candidate genes for F4acR

Susceptibility to enterotoxigenic Escherichia coli with fimbriae F4ac is dominantly inherited in the pig. A three-generation pedigree was created to refine the position of F4acR on chromosome 13 comprising 202 pigs: eight parents, 18 F1 and 176 F2 pigs. The 17-point analysis indicates that F4acR lies between Sw207 and S0283. Recombinant offspring specify that the most probable order is Sw207-S0075-F4acR-Sw225-S0283. We observed six phenotypes for the three fimbrial variants F4ab, F4ac and F4ad. The two missing phenotypes F4abR-/F4acR+/F4adR+ and F4abR-/F4acR+/F4adR- indicate that pigs susceptible to F4ac are always susceptible to F4ab. Furthermore, a weak and a strong adhesion of F4ab and F4ad bacteria was observed. The weak receptor F4abR (F4abRw) was present only in pigs devoid of the receptor F4acR (F4abR+/F4acR-). In contrast, in pigs with the phenotype F4abR+/F4acR+, F4ab bacteria adhered to the majority of enterocytes. F4abRw constitutes a frequently observed phenotype whose inheritance is still unclear. Strong adhesion of F4ab and F4ac bacteria is most likely influenced by the same receptor that we name F4bcR. The number of F4ad bacteria that adhered to enterocytes was very variable in the adhesion test. Moreover, expression of F4adR was independent of age. Our segregation analyses indicated a dominant inheritance of F4adR, although the number of susceptible pigs was smaller than expected. We examined four genes as candidates for the F4acR locus: the transferrin receptor gene (TFRC) and three genes members of the glucosyl/galactosyltransferase family (B3GnT5, B3GALT3 and B4GALT4). Comparison of sequences from resistant and homozygous susceptible F4ac pigs did not reveal any causative single nucleotide polymorphism in the four genes. Two silent mutations at the positions 295 (C/T) and 313 (T/C) in B3GALT3 were found. Using the somatic cell hybrid panel, B3GnT5 and B3GALT3 were assigned to the chromosomal region SSC13q23-q41. No mutations were found in the cDNA sequences of these genes associated with the F4acR genotypes.

Cytogenetic comparison of saola (Pseudoryx nghetinhensis) and cattle (Bos taurus) using G- and Q-banding and FISH

In order to cytogenetically describe the new bovid species saola (Pseudoryx nghetinhensis), comparative G- and Q-banding of saola and cattle (Bos taurus) chromosomes as well as FISH-mapping of 32 type-I markers (29 Texas markers and three additional markers) on saola chromosomes were performed. Saola was shown to have a diploid number of 2n = 50 chromosomes possessing five biarmed autosomal pairs and an acrocentric X chromosome. Homology of saola and cattle chromosomes was indicated by banding patterns and by marker hybridization suggesting that all five biarmed pairs in saola originate from centric fusions involving ten cattle autosomes. However, small intrachromosomal rearrangements cannot be excluded. In this study the first preliminary homology map of these two species is presented.

Application of bovine microsatellite markers for genetic diversity analysis of Swiss yak (Poephagus grunniens)

In order to assess the applicability of bovine microsatellite markers for population genetic studies in Swiss yak, 131 bovine microsatellite markers were tested on a panel of 10 animals. Efficient amplification was observed for 124 markers (94.6%) with a total of 476 alleles, of which 117 markers (94.3%) were polymorphic. The number of alleles per locus among the polymorphic markers ranged from two to nine. Seven loci (ILSTS005, BMS424B, BMS1825, BMS672, BM1314, ETH123 and BM6017) failed to amplify yak genomic DNA. Two cattle Y-chromosome specific microsatellite markers (INRA126 and BM861) amplified genomic DNA from both male and female yaks. However, two additional markers on cattle Y-chromosome (INRA124 and INRA189) amplified DNA from only males. Of the polymorphic markers, 24 microsatellites proposed by CaDBase for within- and cross-species comparisons and two additional highly polymorphic markers (MHCII and TGLA73) were used to investigate the genetic variability and the population structure of a Swiss yak herd that included 51 additional animals. The polymorphic information content ranged from 0.355 to 0.752, while observed heterozygosity (HO) ranged from 0.348 to 0.823. Furthermore, a set of 13 markers, organized into three multiplex polymerase chain reactions, was evaluated for routine parentage testing. This set provided an exclusion probability in a family of four yaks (both parents and two offspring) of 0.995. These microsatellites serve as useful tools for genetic characterization of the yak, which continues to be an important domestic livestock species.

Characterization of G-banded chromosomes of a female saola (Pseudoryx nghetinhensis,2n = 50) and X chromosome i dentification by means of fluorescent in situ hybridization

The saola (Pseudoryx nghetinhensis) is a newly discovered large mammal species, belongs to the subfamily Bovinae and is listed as being endangered. Due to the limitation of the material available, no cytogenetic studies have been carried out on this species. In the present study, preliminary cytogenetic analysis was undertaken on cultured female fibroblast cells to characterize the karyotype organization of saola. An examination of 120 Giemsa stained metaphases showed the diploid chromosome number of 2n = 50, including five bi-armed chromosome pairs. The distribution of constitutive heterochromatin in saola was studied. However, the variability in the size of C-bands was not significant on all the homologous chromosomes. The X chromosome pair, corresponding to the largest telocentric chromosomes, was identified by fluorescent in situ hybridization (FISH) using a bacterial artificial chromosome clone (BAC 0577G05, which maps to BTAXq25-->q33). In comparison to the standard karyotype of cattle (ISCNDB 2000), a G-banded ideogram of saola (about 390 band level) was presented. This work, therefore, provided a basic insight into the karyotype organization of this endangered species and will be particularly useful to improve the understanding of differences of genomes between related species.

Application of bovine microsatellite markers on Saola (Pseudoryx nghetinhensis)

The aim of the present study was to assess the applicability of bovine microsatellite markers on Saola (Pseudoryx nghetinhensis). A total of 127 microsatellite markers were tested on a male and a young female Saola. An efficient amplification was observed for 123 markers (96.8%), 73 markers (59.3%) were polymorphic. Four loci (BM2304, BMS1928, BMS779 and ILSTS006) on cattle chromosomes 1, 4, 7 and 8, respectively, failed to amplify in Saola. Two cattle Y-chromosome-specific microsatellite markers (INRA126 and BM861) were successfully amplified from both sexes in Saola. However, two additional markers (INRA124 and INRA189) on Y-chromosome failed to amplify in the female animal. These results show that most of the bovine microsatellite markers are applicable in Saola and therefore they can be used to study the phylogenetic relationships and the genetic diversity of the Saola population.

Comparative chromosomal studies of E. caballus (ECA) and E. przewalskii (EPR) in a female F1 hybrid

Previous research revealed that the karyotypes of Equus przewalskii (2n = 66) and Equus caballus (2n = 64) differ by one pair of metacentric chromosomes, present in ECA but not in EPR, and two pairs of acrocentric chromosomes found only in the EPR karyotype. The formation of a trivalent during meiosis in a male F1 hybrid and the homologies in G-banding patterns suggest that ECA 5 corresponds to two acrocentric EPR chromosomes resulting from a Robertsonian fusion or fission event. Chromosomal investigations of a female interspecies F1 hybrid including banded karyograms and fluorescence in situ hybridization (FISH) studies focusing on the p and q arm of ECA 5 were conducted. Q- and G-banding patterns of E. caballus, E. przewalskii and the hybrid revealed interspecies homology between all chromosome pairs except for ECA 5, EPR 23 and EPR 24, which were unique for that particular species. Furthermore, they indicated homology between ECA 5p and EPR 23 as well as between ECA 5q and EPR 24. FISH revealed hybridization of the BACs laminin beta 3 (LAM B3) and laminin gamma 2 (LAM C2) to ECA 5p and EPR 23. However, nuclear factor I (NFIA) and immunoglobulin lambda (IGL@), primarily assigned to ECA 5q, mapped to ECA 7 and EPR 6 respectively. Thus the karyotypes of E. caballus and E. przewalskii differ solely by one Robertsonian translocation (ECA 5 =EPR 23 + EPR 24).

Bayesian inference on major loci in related multigeneration selection lines of laying hens

A mixed inheritance model, postulating a polygenic effect and differences between the 3 genotypes of a biallelic locus, was fitted separately to the data of 2 multigeneration selection lines and a control evolving from a common base population. Inferences about the model were drawn from the application of the Gibbs sampler. Body weight at 20 and 40 wk (BW20, BW40) and average egg weight to 40 wk (EW40) were included in the analyses. Significance of differences between posterior means of parameters was established by comparing their 95% highest probability density regions. Significant (P < 0.05) additive and dominance effects due to the genotypes at the major locus were found for all traits. The allele causing a lower trait value was the (partial) dominant one in all traits, leading to a negative dominance effect. The additive variance due to the major locus was also significant, i.e., greater than zero (P < 0.05) in all traits, whereas the dominance variance was only important for EW40. With the exception of the residual variances of one selection and the control line, no (P > 0.05) differences of posterior means of any parameter could be observed between lines. No significant genotypic or polygenic selection response was found for BW40. On the contrary, both genetic responses were found significant for EW40 in the selected lines, but not in the control. No differences (P > 0.05) between lines could be observed for the derived frequencies of the allele causing the higher trait value and the frequencies of one homozygote and the heterozygote genotypes at the major locus. The detection of a major locus with relatively modest effect confirmed that this type of analysis with data from selected lines was indeed powerful.

cDNA cloning, mapping and polymorphism of the porcine Rhesus (RH) gene

The Rhesus (Rh) gene superfamily in humans and mice contains four independent genes, RH, RHAG, RHBG, and RHCG/GK. Heretofore, only the RHBG cDNA has been cloned in pig. We have isolated the porcine RH cDNA; its complete open reading frame of 1269 nucleotides encoded 423 amino acids. Porcine RH protein shared 67.6% amino acid identity with bovine RH, 61.0% with human RhCE and 60.8% with human RhD. The RT-PCR revealed RH transcripts in the spleen and bone marrow, but not in the heart, kidney, or lung. In RH intron 4, a deletion of 17 nucleotides distinguished the shorter allele (allele 1) from the longer. As determined in 115 unrelated pigs from five breeds - Landrace (L, n = 23), Large White (LW, n = 28), Duroc (D, n = 24), Hampshire (H, n = 20) and Piétrain (n = 20) - allele 1 frequencies were 1.0 (L, H), 0.77 (LW), 0.70 (P) and 0.25 (D). Somatic cell hybrid mapping localized the porcine RH and RHBG genes to pig chromosomes 6q22-q23 and 4q21-q22, respectively. Genetic mapping suggested RH-(FUT1, S, GPI, EAH, A1BG)-PGD as the most probable locus order. Sequence homology, mapping data, and haematopoietic tissue expression suggest that this cDNA may indeed encode the porcine RH homologue.

[Microdissection of chromosomes in veterinary medicine]

Microdissection of chromosomes and subsequent amplification of the DNA material by PCR allow the development of libraries, region-specific DNA probes or chromosome painting probes. Veterinary medicine will benefit from this method in instances where clarification of numercal or structural chromosome aberrations is needed.

Fine-mapping of the intestinal receptor locus for enterotoxigenic Escherichia coli F4ac on porcine chromosome 13

The aim of this study was to refine the localization of the receptor locus for fimbriae F4ac. Small intestinal enterocyte preparations from 187 pigs were phenotyped by an in vitro adhesion test using two strains of Escherichia coli representing the variants F4ab and F4ac. The three-generation pedigree comprised eight founders, 18 F1 and 174 F2 animals, for a total of 200 pigs available for the linkage analysis. Results of the adhesion tests on 171 F2 pigs slaughtered at 8 weeks of age show that 23.5% of the pigs were adhesive for F4ab and non-adhesive for F4ac (phenotype F4abR+/F4acR-; R means receptor). Pigs of this phenotype were characterized by a weak adhesion receptor for F4ab. No pigs were found expressing only F4acR and lacking F4abR. Receptors for F4ab and F4ac (F4abR+/F4acR+) were expressed by 54.5% of the pigs. Animals of this phenotype strongly bound both F4ab and F4ac E. coli. In the segregation study, the serum transferrin (TF) gene and 10 microsatellites on chromosome 13 were linked with F4acR (recombination fractions (theta) between 0.00 and 0.11 and lod score values (Z) between 11.4 and 40.4). The 11-point analysis indicates the F4acR locus was located in the interval S0068-Sw1030 close to S0075 and Sw225, with recombination fractions (theta) of 0.05 between F4acR and S0068, 0.04 with Sw1030, and 0.00 with S0075 and Sw225. The lack of pigs displaying the F4abR-/F4acR+ phenotype and the presence of two phenotypes for F4abR (a strong receptor present in phenotype F4abR+/F4acR+ and a weak receptor in phenotype F4abR+/F4acR-) led us to conclude that the receptor for F4ac binds F4ab bacteria as well, and that it is controlled by one gene localized between S0068 and Sw1030 on chromosome 13.

[Horse breeding: genetic tests for the coat colors chestnut, bay and black. Results from a preliminary study in the Swiss Freiberger horse breed]

Coat color played an important role during domestication and formation of breeds. Livestock breeders often had special preferences for particular color phenotypes because they believed them to be associated with performance or fitness traits. Socio-cultural reasons might have had an influence on color selection as well. Recently genetic tests on DNA level got available to genotype in any individual horse for basic horse coat colors (chestnut, bay, black). In particular, hidden carriers of the recessive chestnut and black allele are recognizable with these tests. A sample of 162 Franches-Montagnes horses from Switzerland was genotyped for the alleles for chestnut and black. The analysis of allele frequencies revealed a high prevalence of the chestnut allele and a low frequency of the black allele in this population. Rare colors are in demand on the market. The statistical analysis of 1369 offspring from five stallions indicate, that darker shades of basic color phenotypes (dark chestnut, dark bay) follow a recessive mode of inheritance in the Franches-Montagnes horse breed.

[Microsatellite analysis in a population of Baudet du Poitou donkeys]

A population of Baudet du Poitou donkeys was genetically characterized using microsatellites. The results were used to verify the pedigrees and to estimate the genetic variability. It could be confirmed that a equine parentage test kit works well for donkeys and that by using 13 microsatellites more than 99% of wrong pedigree informations would be detected. The genetic variability was comparable to a representative group of Baudet du Poitou donkeys in France.

[Schistosoma reflexum in a female bovine fetus with synaptonemal complex abnormalities]

In this study we present mitotic- and meiotic investigations in an anatomical abnormal bovine fetus. The abnormality could be classified as "schistosoma reflexum", which was never described in fetuses in the literature. In the mitotical chromosome preparations from fibroblast cultures the examined fetus showed no chromosomal difference in comparison to the standard synaptonemal complexes (SC) which were prepared from the fetus at the age of 92 days post coitum. In the SCs from the abnormal fetus 43.75% of the investigated cells showed abnormalities such as "loop," "nonhomologue pairing" and "multivalency" in the pairing behavior of the chromosomes. In comparison, less than 5% of the cells in normal embryos showed such abnormalities.

Molecular and pharmacological characterisation of the MSH-R alleles in Swiss cattle breeds

The coat colour in mammals is determined by the relative amounts of eumelanin (black/brown) and phaeomelanin (red/yellow), produced in melanocytes, which are controlled by melanocyte stimulating hormone receptor (MSH-R). Melanocyte stimulating hormone receptor is activated by alpha-melanocyte-stimulating hormone (alpha-MSH). Stimulated MSH-R activates adenylyl cyclase (AC), thereby increasing the amount of cyclic AMP in the cell, which activates the enzyme tyrosinase resulting in eumelanin synthesis. In this study the complete coding sequences of five alleles of the MSH-R gene found in Holstein, Red Holstein, Simmental, and Brown Swiss cattle were cloned into a mammalian expression vector and transfected into human embryonic kidney (HEK) 293 cells. The expressed receptors were analyzed for their ability to increase intracellular cAMP in response to stimulation by alpha-MSH. The recessive red allele (e) found in Red Holstein and Simmental and the dominant black allele (ED) found in Holstein were unresponsive to a wide range of alpha-MSH concentrations. Two alleles from Brown Swiss (E(d1), E(d2)) and one allele found in the Simmental breed (e(f)) responded to stimulation by alpha-MSH in a dose-dependent manner. When compared to E(d1) and E(d2), the cells transfected with the e(f) MSH-R allele, however, reached the corresponding intracellular cAMP concentrations at a 10-fold higher concentration of alpha-MSH. In conjunction with the mode of inheritance of coat colour, the results indicate that the e MSH-R allele is a non-functional receptor, E(D) is constitutively activated receptor, and E(d1) and E(d2) are hormonally activated receptors. The delay in e(f) MSH-R response may explain the similarity between the e and e(f) phenotypes.

Tumor regression induced by intratumoral injection of DNA coding for human interleukin 12 into melanoma metastases in gray horses

Preclinical studies investigating new therapeutic principles against melanoma are presently being carried out in mouse models; however, these are not optimal. Here we describe a novel animal model using gray horses. These animals spontaneously develop metastatic melanoma that resembles human disease and is thus highly relevant for preclinical studies testing new immunotherapy protocols. We found that injection of plasmid DNA coding for the human cytokine interleukin 12 into established metastases induced significant regression in all 12 treated lesions in a total of 7 horses. Complete disappearance was observed in one treated lesion, with no recurrence after 6 months. No adverse events have been observed in any of the animals during and after treatment. These results demonstrate the effectiveness and safety of interleukin 12 encoding plasmid DNA therapy against established metastatic disease in a large animal model and serve as a basis for a clinical trial.

[Genomic methods for identification of traits and inherited disorders in farm animals]

In this review we demonstrate the interaction of the blueprint of an individual (the genome, genomic DNA), its phenotype and the environment. The phenotype consists of quantitative (e.g. growth, milk yield) or functional characteristics e.g. fitness, longevity, fertility and disease resistance. The latter characteristics influence the welfare of an animal substantially. As only the genetically determined part of a particular characteristic is transferred from one generation to the next, it is important to know what the genetic variants (alleles) of the parents at one or more gene loci are. New methods in molecular biology have made it possible to localize and characterize important genes which help to breed more efficient and healthy animals. The exact characterization of the phenotype is vital in identifying genes with major effects and therefore the cooperation with experts from veterinary medicine, biochemistry, and biology is indispensable. As well as an overview of available genetic tests in farm animals, we show various examples how to identify the molecular basis of a particular phenotype and how to use the results in practical breeding programs. Genetic diagnosis enables the breeder to identify undesired alleles early and hinders therefore its uncontrolled distribution in the population. In the long term this leads to a smaller number of affected animals and depending on the disease it may help to prevent animals from suffering.

Mit Liposomen unterstützte Leukozytenkulturen und Standardisierungsversuche für zytogenetische Präparationen

Abstract. Title of the paper: Liposome supported leukocyte eultures and standardisation for zytogenetic preparations There are considerable difficulties in making constant and qualitatively good chromosomal preparations from breeding animals. Varying animal material (without special management information), ingredients of the media, mitogenes, or different qualities of fetal calf serum are all influencing factors. We made experiments with liposomes, which have shown in the literature lo improve the quality of chromosomal preparations. There are only a few examinations reported about optimizing the culture conditions for short term cultures, including the following chromosomal preparations as well. These experiments have shown that fetal calf serum cannot be replaced by liposomes and the mitogene is obligatory for metaphases.

Picogram cloning and direct in situ sequencing of DNA from gel pieces

We describe a simple and rapid procedure for cloning and sequencing of DNA fragments separated by gel electrophoresis, using novel hydrophilic gels, Clearose BG, Spreadex, and Poly(NAT), that do not melt at 95 degrees C. For cloning, a band of interest is excised precisely and incubated in an extraction buffer containing 5-10 mM MgCl2 at 70 degrees C for 15-45 min. The eluted DNA is added directly to the plasmid solution. Using a topoisomerase-based ligation system, we were able to transform bacteria with a few picograms of DNA and isolate recombinant clones. For in situ sequencing, the DNA in the gel serves as the template. No treatment before cycle sequencing is necessary for fragments up to 500 bp.