Search PubMedSearch

Biomedical subjects

A Van Zeveren

Publications and source records attributed to A Van Zeveren.

At least 19 recordsLinked to original sources

Comparative mapping between human chromosome 3 and porcine chromosome 13.

Zoo-FISH and somatic cell hybrid panels have earlier demonstrated extended synteny conservation between human chromosome 3 (HSA3) and pig chromosome 13 (SSC13). In the present study, eight human genes viz., ADCY5, CASR, COL7A1, COL8A1, ITIH1, RHO, SIAT1 and XPC, spread along the length of HSA3, were chosen for expanding the comparative map between the two chromosomes. Using human and rat cDNAs, or human- and porcine-specific PCR products as probes, 8 porcine lambda clones were isolated. After subcloning and partial sequence determination, identity of the clones with regards to the specific genes was established. The eight type 1 markers thus obtained were biotin labeled and FISH mapped to pig metaphase spreads. All lambda clones localized to SSC13. In combination with the hitherto published mapping data of coding sequences on SSC13, a preliminary comparative status depicting the relative organization of this chromosome with respect to HSA3 was developed. The comparative map thus obtained bears significance in searching for candidate genes of economically important traits mapped to SSC13.

Adenylyl Cyclases

Effectiveness of bovine microsatellites in resolving paternity cases in American bison, Bison bison L.

A set of 33 cattle microsatellite primer pairs was tested with the DNA of American bison from a captive population in Belgium and evaluated for usefulness in parentage testing. Two primer sets did not amplify and three were monomorphic. Among the polymorphic markers, the number of alleles ranged from two to nine. Heterozygosity, polymorphism information content (PIC) and probability of exclusion (PE) values were low by comparison with those obtained with the same markers in cattle. Two methods of estimating PE were used, one which assumed equal allele frequencies between parental sexes and another which took into account differences in allele frequencies between parental sexes. An internationally accepted set of nine microsatellites gives cumulative PE values of 0.98 and 0.97, respectively, for the two methods. The potential of this marker set to identify bison x cattle hybrids is discussed. Because bison and cattle have a common ancestor, these microsatellites are a useful way to establish genetic distances and can lead to the construction of phylogenetic trees.

Alleles

Evaluation of the genetic variability of 23 bovine microsatellite markers in four Belgian cattle breeds.

The polymorphism of 23 microsatellites in the four main cattle breeds in Belgium (Holstein Friesian, Belgian Blue, Belgian Red Pied and East Flemish) was analysed. Heterozygosity, polymorphism information content, the effective number of alleles, exclusion probability and the probability of genotypic identity for two random individuals were calculated for all microsatellites and all breeds. The Belgian Blue breed is generally a little less polymorphic in comparison with the other three breeds. Estimates of the genetic distances between these breeds confirmed the widely accepted proposition that the Belgian Blue is the most genetically distinct of these breeds. The three other breeds are likely to become one population, given current breeding strategies. Exclusion probabilities in parentage control cases are > 0.9999 in all four breeds when all 23 microsatellites are used and > 0.98 with only the two most polymorphic multiplexes.

Animals

A detailed physical map of the porcine major histocompatibility complex (MHC) class III region: comparison with human and mouse MHC class III regions.

A detailed physical map of the porcine MHC class III region on Chr 7 was constructed with a panel of probes in a series of hybridizations on genomic pulsed field gel electrophoresis (PFGE) Southern blots. A precise organization of the 700-kb segment of DNA between G18 and BAT1 can now be proposed, with more than 30 genes mapped to it. Comparison of this region with homologous regions in human and mouse showed only minor differences. The biggest difference was observed in the CYP21/C4 locus with only one CYP21 gene and one C4 gene found, whereas in human and mouse these genes are duplicated. These results show the class III region is very well conserved between pig, human, and mouse, in contrast with the class I and class II regions, which seem more prone to rearrangements.

Animals

Conservation of the RD-BF-C2 organization in the pig MHC class-III region: mapping and cloning of the pig RD gene.

The RD gene, named after the arginine (R) and aspartic acid (D) repeat in the central part of its protein, was initially mapped in the mouse H-2S subregion between C4 and BF. It was later mapped in the same position in the human MHC and here we show it is also conserved in the pig MHC class III region, close to the complement BF gene. A pig RD genomic clone was isolated from a lambda-phage library. Hybridizations on genomic DNA separated with pulsed field gel electrophoresis identified common 220 kb NruI, 130 kb EagI and 200 kb MluI bands for RD, BF and C2. The RD gene has also a 17 kb Kp nI and 11 kb SacI fragment in common with BF but not with C2. The close linkage of the RD and BF genes was further established by hybridization of BF to a genomic lambda-phage clone also containing the RD gene. This genomic RD clone overlaps with a lambda-phage clone previously isolated and containing the complete BF gene and the 3' part of C2. The distance between RD and BF is about 6 kb. The junction between the two complement genes BF and C2 was sequenced and the BF 5' promoter region, overlapping the 3' noncoding region of C2, was compared with that of the human BF promoter. The overall homology was about 80% and all but one identified promoter elements were found in the same position in both genes. The results obtained demonstrate the RD-BF-C2 organization is strongly conserved between human, mouse and pig. No polymorphisms were detected in either the RD gene or in the BF promoter region using polymerase chain reaction and restriction fragment polymorphism analysis.

Amino Acid Sequence

The BAT1 gene in the MHC encodes an evolutionarily conserved putative nuclear RNA helicase of the DEAD family.

The BAT1 gene has previously been identified about 30 kb upstream from the tumor necrosis factor (TNF) locus and close to a NF kappa b-related gene of the nuclear factor family in the major histocompatibility complex (MHC) of human, mouse, and pig. We now show that the BAT1 translation product is the homolog of the rat p47 nuclear protein, the WM6 Drosophila gene product, and probably also Ce08102 of Caenorhabditis elegans, all members of the DEAD protein family of ATP-dependent RNA helicases. This family has more than 40 members, including the eukaryotic translation initiation factor-4A (eIF-4A), the human nuclear protein p68, and the Drosophila oocyte polar granule component vasa. BAT1 spans about 10 kb, is split into 10 exons of varying length, and encodes a protein of 428 amino acids (approximately 48 kDa). Human and pig BAT1 cDNAs display 95.6% identity in the coding region and 80% identity in the 5' and 3' noncoding regions. Several repeat sequences of different types were identified in introns of the porcine BAT1 gene. Three different mRNAs, 4.1, 1.7, and 0.9 kb, respectively, were detected in all tissues analyzed upon hybridization with porcine BAT1 cDNA. Transfection and expression of human BAT1 cDNA after tagging with a heterologous antibody recognition epitope revealed a nuclear localization of the hybrid protein. An MspI RFLP was detected in an SLA class I typed family, confirming the localization of the BAT1 gene in the porcine MHC. BAT1 thus encodes a putative nuclear ATP-dependent RNA helicase and is likely to have an indispensable function.

Amino Acid Sequence

Polymorphic CAC/T repetitive sequences in the pig genome 1.

Three genomic clones were isolated from a size-selected pig DNA library by hybridization with a DNA-fingerprint probe. Analysis at the sequence level revealed that all three clones contain interrupted stretches of triplet repeats mainly composed of CAC and CAT triplets. Evaluation of the corresponding loci for polymorphism by Southern blot hybridization showed considerable length variation. For two loci the polymorphism was also demonstrated by polymerase chain reaction (PCR) amplification. The PiGMaP reference pedigree was typed for all three loci.

Animals

Characterization of porcine polymorphic microsatellite loci.

Twenty-seven (CA)n and two (GA)n microsatellite clones were isolated out of a size-selected genomic pig library. These were sequenced and the number of uninterrupted dinucleotides was found to range from 12 to 26. Flanking primers were chosen for 11 dinucleotide repeats and optimal conditions for polymerase chain reaction (PCR) amplifications were established. Different microsatellite loci were amplified simultaneously by combining primer sets. Related and unrelated pigs were screened for length polymorphisms of the different microsatellite loci. The polymorphic information content (PIC) of these loci ranged between 0.62 and 0.83. Segregation studies in pig reference families established Mendelian inheritance. Locus S0022 was found to be X-linked.

Alleles

Bioavailability of two ibuprofen oral paste formulations in fed or nonfed ponies.

The bioavailability and pharmacokinetics of ibuprofen, a nonsteroidal antiinflammatory drug, was studied in healthy Shetland ponies. Ibuprofen was administered IV, as a suspension, and as a solid solution oral paste to ponies from which food was withheld. The suspension paste was also administered to ponies that received hay and water ad libitum. Both formulations had an absolute bioavailability of about 80%. Bioavailability was not influenced by feeding.

Administration, Oral

A hypervariable pig DNA fragment.

A new hypervariable tandem repeat was isolated from the pig genome and characterized by DNA sequence. The use of this DNA fragment as a probe in order to follow allelic segregation and DNA fingerprinting in pigs, horses and rabbits is documented.

Animals

Swine lymphocyte alloantigens (SLA) class I serology and genetics in Belgian Landrace and Pietrain breeds.

Eighty anti-SLA class I reagents were prepared resulting from skin graft and subcutaneous immunizations in 320 fattening pigs of the Belgian Landrace and Pietrain breeds. By means of these alloantisera seven internationally and five locally established specificities were recognized. Three of the locally assigned specificities were new: BM 36, BM 37 and BM 38. They were serologically and genetically defined. The typing battery was completed with French and Danish reagents, and correlation coefficients were calculated for the main alloantisera recognizing SLA class I alloantigens observed in the Belgian breeds. The SLA haplotype frequencies were estimated in 372 Belgian Landrace and 369 Pietrain pigs. The SLA haplotype distribution differs significantly between both breeds and the genetic distance (0.54) at the SLA system is quite high.

Animals

Evolutionary conservation of the linkage between the structural loci for serum albumin and vitamin D binding protein (Gc) in cattle.

Evidence is presented for close genetic linkage between the structural loci for serum albumin and the vitamin D binding protein (Gc) in Belgian Blue and White cattle. Five recombinants were observed in a total of 342 informative offspring. The recombination frequency between the two loci was estimated as 1.5% +/- 0.9. The observed distribution of the haplotypes deviated from the expected one in the population, probably due to selection and significant linkage disequilibrium.

Animals

Equine lymphocyte antigens in four major Belgian horse populations. Contribution to serology and antigen distribution.

158 Belgian Saddlebreds, 130 Belgian Trotters, 108 Belgian Draft horses and 92 Shetland ponies have been typed for serologically defined antigens at the ELA and ELY systems. Gene frequencies were estimated in each breed for the internationally established ELA, ELY-1 and ELY-2 alleles as well as for locally assigned additional ELA markers and for subtypes of ELA-W3, W9 and W11. The distribution of ELA alleles was in agreement with the expected Hardy-Weinberg equilibrium for the 4 horse breeds described here. Differences in gene frequencies between these main Belgian horse populations were observed.

Alleles