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W A van Haeringen

Publications and source records attributed to W A van Haeringen.

6 recordsLinked to original sources

Detection of universal variable fragments as markers for genetic studies. A novel technology for DNA fingerprinting.

A novel DNA technology enables the detection of universal variable fragments (UVF), thus revealing genetic variation without a priori sequence information. The detection of UVF markers is based on two amplifications of genomic DNA with the polymerase chain reaction. In the first amplification, two short oligonucleotide primers produce a large number of fragments. One primer is based on a microsatellite sequence, whereas the second primer can have any sequence. In the second amplification, the length of the primers is increased in order to decrease the number of amplicons. This enables the selection of polymorphic fragments. Restriction digestion can be used to further increase the number of polymorphisms. Until now, we have demonstrated UVF in several different species. In addition, with the present study we have contributed to the linkage map of the rabbit by localizing 11 UVF markers on different linkage groups. Mendelian inheritance was shown in this linkage study through a backcross of two inbred rabbit strains. The power of the UVF technique is based on the selection for microsatellite variation in combination with the detection of single-nucleotide polymorphisms. UVF thus offers the possibility of increasing the clustering of markers and localizing genes in species for which sequence information is either not present or only scarcely present.

Animals↗

Heterozygosity excess at the cattle DRB locus revealed by large scale genotyping of two closely linked microsatellites.

A method for MHC DRB typing in cattle based on two closely linked and highly polymorphic microsatellites is described. The two microsatellites DRBP1ms and DRB3ms are located in intron 2 of the corresponding DRB gene. The very strong linkage disequilibrium between the two loci made it possible to establish DRB microsatellite haplotypes. The typing results with this method on reference samples followed closely that obtained with RFLP and direct sequence analysis of DRB3 exon 2. The method is well suited for large scale genotyping and was successfully applied for typing more than 600 unrelated animals representing 23 breeds. The data were used to test whether the observed DRB allele frequency distributions were consistent with that expected for selectively neutral alleles in populations at mutation-drift equilibrium. A significant heterozygosity excess was detected and there was an obvious trend across breeds towards a more even allele frequency distribution than expected. The deviation may be due to balancing selection acting on the DRB locus or by recent population bottlenecks.

Alleles↗

[Control of the identity of blood samples for the surveillance of research on swine vesicular disease and Aujeszky's disease].

A surveillance programme for swine vesicular disease (SVD) and Aujeszky disease was set up in 1993 in the Netherlands. Blood samples are taken from pigs by local veterinarians to enable testing for the presence of antibodies against these viruses. A programme to guarantee the identity of pigs tested for these diseases has been in operation since late 1995. In this programme, pigs are identified on the basis of the DNA profiles of blood and hair samples. The hair samples are collected by the department of Animal Health Control. Analysis proves whether blood and hair samples are from the same animal. A total of 655 animals have been tested from 94 farms. In 38.6% of these farms differences were found between blood and hair samples.

Animal Identification Systems↗

Polymorphic microsatellite DNA markers in the rabbit (Oryctolagus cuniculus).

By searching the EMBL nucleotide database a total of 157 rabbit nuclear gene microsatellites were obtained (VAN LITH and VAN ZUTPHEN, Animal Genetics 27, 387-395, 1996). Thirteen of these were analysed by PCR to examine the degree of polymorphism of the amplified fragments in rabbits from different breeds. The 13 pairs of primers resulted in polymorphic products with an average of four alleles per microsatellite sequence (ranging between 2-11). There was a positive relationship between the longest repeat unit number in the nucleotide sequence and the number of alleles detected. The results obtained so far justify the conclusion that rabbit microsatellites extracted from the EMBL nucleotide sequence database are sufficiently polymorphic to be useful as Type 1 markers in rabbit genetic studies.

Alleles↗