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A Eggen

Publications and source records attributed to A Eggen.

75 records · Page 5Linked to original sources

A cosmid specific for sequences encoding a microtubule-associated protein, MAP1B, contains a polymorphic microsatellite and maps to bovine chromosome 20q14.

A clone for the bovine gene MAP1B was isolated from a bovine cosmid library with a probe obtained by cross-species PCR. The single positive cosmid clone was localized by FISH to chromosome region 20q14. Analysis of the cosmid revealed the presence of a microsatellite motif with a two-allele polymorphism detectable by PCR amplification of genomic DNA. However, the analysis of this polymorphism in a bovine family affected by SMA indicated absence of very close linkage of the phenotype for bovine SMA with MAP1B.

Animals↗

Development and assignment of bovine-specific PCR systems for the Texas nomenclature marker genes and isolation of homologous BAC probes.

In 1996, Popescu et al. published the Texas standard nomenclature of the bovine karyotype in which 31 marker genes, already mapped in man, were chosen to permit unambiguous identification and numbering of each bovine chromosome. However, specific PCR systems were not available for each marker gene thus preventing the assignment of part of these markers by somatic cell hybrid analysis. In addition, some difficulties remained with the nomenclature of BTA25, BTA27 and BTA29. In this work, specific PCR systems were developed for each of the marker genes except VIL1 (see results), from either existing bovine or human sequences, and a bovine BAC library was screened to obtain the corresponding BAC clones. These PCR systems were used successfully to confirm the assignment of each marker gene (except for LDHA, see results) by analysis on the INRA hamster-bovine somatic cell hybrid panel. The difficulties observed for LDHA and VIL1 are probably due to the fact that these genes belong to large gene families and therefore suggest that they may not be the most appropriate markers for a standardisation effort. This panel of BACs is available to the scientific community and has served as a basis for the establishment of a revised standard nomenclature of bovine chromosomes.

Animals↗

Construction and characterization of a bovine BAC library with four genome-equivalent coverage.

A bovine artificial chromosome (BAC) library of 105 984 clones has been constructed in the vector pBeloBAC11 and organized in 3-dimension pools and high density membranes for screening by PCR and hybridization. The average insert size, determined after analysis of 388 clones, was estimated at 120 kb corresponding to a four genome coverage. Given the fact that a male was used to construct the library, the probability of finding any given autosomal and X or Y locus is respectively 0.98 and 0.86. The library was screened for 164 microsatellite markers and an average of 3.9 superpools was positive for each PCR system. None of the 50 or so BAC clones analysed by FISH was chimeric. This BAC library increases the international genome coverage for cattle to around 28 genome equivalents and extends the coverage of the ruminant genomes available at the Inra resource center to 15 genome equivalents.

Animals↗