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A Eggen

Publications and source records attributed to A Eggen.

At least 73 records · Page 4Linked to original sources
PubMed1996

T-banding pattern of bovine chromosomes and karyotype reconstitution with physically mapped cosmids.

Bovine T-banded chromosomes were identified by fluorescence in situ hybridization (FISH) using 27 cosmid probes as chromosome landmarks. Pairwise combinations of probes from chromosomes of markedly different size were cohybridized to metaphase spreads of T-banded chromosomes. This confirmed the association of banding patterns to individual chromosomes. The T-banding pattern appears to be related to R-bands: 80% of T-bands were in corresponding position to R-bands, but not always conserved in size. Band assignments placed 20 probes on similar bands in both patterns. The identification of T-banded chromosomes represents a first step toward the construction of a compositional map of the bovine genome and an additional tool for its study on a comparative basis.

Animals↗
PubMed1995

A genetic and physical map of bovine chromosome 3.

This paper reports a map of nine polymorphic microsatellite markers previously assigned to bovine chromosome 3 (BTA3) by somatic cell genetics. The linkage group covers 101 cM on the chromosome with an average intermarker distance of 13.9 cM. One marker (INRA200) was isolated from a peak of flow sorted chromosomes 2 and 3. Another marker (INRA197) was derived from a cosmid. The localization of the cosmid by in situ hybridization enabled the orientation of the linkage group on BTA3. Markers were relatively evenly spaced and consequently can be used to complement other mapping data about this chromosome. This establishes a framework of polymorphic markers that can be used to search for quantitative trait loci (QTL).

Animals↗
PubMed1994

A genetic and physical map of bovine chromosome 11.

A genetic map of bovine Chromosome (Chr) 11 (BTA11, synteny group U16) has been constructed from 330 animals belonging to 21 families, which constitute the international bovine reference panel (IBRP). This map is based on 13 polymorphic microsatellite markers, two of which were chosen in previously published maps. Three markers have been isolated from cosmids. Two of the three cosmids have been physically localized by fluorescence in situ hybridization (FISH), to anchor the genetic map on the chromosome. In addition, a biallelic polymorphism in the beta-lactoglobulin gene (LGB) has been genetically positioned relative to the microsatellite markers. The most probable order of the markers is: cen-INRA044-BM716-INRA177-(TGLA327, INRA198, INRA131)-INRA111-INRABERN169-(INRA115, INRA032)-INRA108-INRABERN162-INRA195-LGB. The total linkage group spans 126 cM, which probably corresponds to most of the chromosome length. The average intermarker distance is about 10.5 cM, allowing the potential detection of a genetic linkage with any Economic Trait Loci (ETL) of this chromosome. Seven of these markers have been previously published by Vaiman and coworkers (1994), two will be published as part of a set of markers (Eggen et al. in preparation), two are described in this paper, and two (BM716, TGLA327) were chosen from the published maps of BTA11 in order to integrate our data with existing maps. All these markers were assigned to synteny group U16 by use of a previously characterized panel of hamster/bovine somatic hybrid cell lines (Guérin et al. 1994).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

The bovine lactoferrin gene (LTF) maps to chromosome 22 and syntenic group U12.

Five overlapping lambda EMBL-clones, containing the complete bovine lactoferrin gene (LTF), have been used to map this gene by fluorescence in situ hybridization to bovine Chromosome (Chr) band 22q24. Primers derived from promoter and exon I sequences were applied in polymerase chain reactions (PCRs) to DNA samples of a previously characterized panel of somatic cell hybrid lines, allowing the assignment of the bovine lactoferrin locus to syntenic group U12. These results permit the assignment of syntenic group U12 to bovine Chr 22.

Animals↗
PubMed1994

A set of 99 cattle microsatellites: characterization, synteny mapping, and polymorphism.

Cattle microsatellite clones (136) were isolated from cosmid (10) and plasmid (126) libraries and sequenced. The dinucleotide repeats were studied in each of these sequences and compared with dinucleotide repeats found in other vertebrate species where information was available. The distribution in cattle was similar to that described for other mammals, such as rat, mouse, pig, or human. A major difference resides in the number of sequences present in the bovine genome, which seemed at best one-third as large as in other species. Oligonucleotide primers (117 pairs) were synthesized, and a PCR product of expected size was obtained for 88 microsatellite sequences (75%). Synteny or chromosome assignment was searched for each locus with PCR amplification on a panel of 36 hamster/bovine somatic cell hybrids. Of our bovine microsatellites, eighty-six could be assigned to synteny groups of chromosomes. In addition, 10 other microsatellites--HEL 5, 6, 9, 11, 12, 13 (Kaukinen and Varvio 1993), HEL 4, 7, 14, 15--as well as the microsatellite found in the kappa-casein gene (Fries et al. 1990) were mapped on the hybrids. Microsatellite polymorphism was checked on at least 30 unrelated animals of different breeds. Almost all the autosomal and X Chr microsatellites displayed polymorphism, with the number of alleles varying between two and 44. We assume that these microsatellites could be very helpful in the construction of a primary public linkage map of the bovine genome, with an aim of finding markers for Economic Trait Loci (ETL) in cattle.

Animals↗
PubMed1994

Assignment of bovine synteny group U2 to chromosome 9.

One cosmid containing a microsatellite (INRA144, D9S14) was assigned to bovine synteny group U2 by somatic cell genetics and localized to bovine chromosome 9q25 by fluorescent in situ hybridization. These results permitted the assignment of one more synteny group to a bovine chromosome. There are now 22 out of 31 bovine synteny groups which are related to a chromosome. The mapping data have been entered in the BovMap database, Jouy-en-Josas, France.

Animals↗
PubMed1994

Bovine synteny group U7, previously assigned to G-banded chromosome 25 in the ISCNDA nomenclature, assigns to R-banded chromosome 29.

Four microsatellite-containing bovine cosmids have been regionally localized by fluorescence in situ hybridization to bovine R-banded chromosome 29 (BTA29) and to the 1;29 translocated chromosomes. PCR-analyses of a somatic hybrid cell panel assigned the four microsatellites to synteny group U7. One of the cosmids (IDVGA7) has been previously mapped to G-banded BTA25 allowing to assign U7 to this chromosome. Hence, it is concluded that G-banded BTA25 corresponds to R-banded BTA29. The occurrence of other misleading nomenclatures for small bovine chromosomes is discussed.

Animals↗
PubMed1994

Further characterization of a somatic cell hybrid panel: ten new assignments to the bovine genome.

Thirty-six partially characterized hamster-bovine hybrid cell lines were used for the determination of synteny groups. Sixteen additional reference loci, selected for their coverage of the bovine genome, were analysed on these hybrid cells. This increases to 25 the number of synteny groups detected. This panel was then used to make synteny assignments for 10 additional loci, eight by Southern blotting (COL1A1, COL1A2, FAS, CTSB, CTSL, CHRNG, HEXB and HTR1A) and two by polymerase chain reaction (PCR) amplification (HRH1 and ETH1112). These loci were assigned to international synteny groups U12 (HRH1), U13 (COL1A2), U17 (CHRNG), U21 (COL1A1, FAS), U29 (ETH1112), to chromosome 20 (U14 or U25) for HEXB and HTR1A, and to the same local synteny group (A), which is probably U18, for CTSB and CTSL. For three loci already mapped in humans (COL1A1, COL1A2 and CHRNG), the present results are in accordance with the predictions based on comparative mapping between the human and bovine species.

Animals↗
PubMed1993

Isolation and mapping of polymorphic microsatellites in cattle.

A partial plasmid library with bovine genomic inserts of about 500 basepairs was screened with a (dC-dA)n.(dG-dT)n oligonucleotide probe for the repeated nucleotide motif (CA)n. Eleven positive clones (0.3% of all colonies screened) were discovered and were subsequently isolated and sequenced. Eight microsatellite loci were analysed, one with eight alleles, one with seven alleles, three with six alleles, one with three alleles and two with two alleles. Six of these microsatellites were mapped by PCR-analysis of a panel of somatic hybrid lines.

Alleles↗
PubMed1992

RASA contains a polymorphic microsatellite and maps to bovine syntenic group U22 on chromosome 7q2.4-qter.

The bovine gene for the p21ras protein activator (RASA) includes in its 5' untranslated region a (TG)n repeat. Analysis of this (TG)n repeat by PCR amplification of genomic DNA revealed a four-allele polymorphism. A cDNA probe was used to assign RASA to the region 2.4-qter of bovine Chromosome (Chr) 7 by in situ hybridization. PCR analysis of a panel of somatic hybrid lines allowed the assignment of RASA to the unassigned syntenic group 22 (U22) and thus localizes U22 on Chr 7.

Animals↗
PubMed1992

Mapping of bovine markers CYP21, PRL, and BOLA DRBP1 by genetic linkage analysis in reference pedigrees.

We have analyzed DNA from 13 bovine reference pedigrees using primers specific for microsatellite markers derived from the 21-steroid hydroxylase (CYP21) and prolactin (PRL) genes and the leukocyte antigen (BOLA DRBP1) pseudogene. Linkage was demonstrated between PRL and BOLA DRBP1 (theta = 0.05; Z = 19.6), cyp21 and PRL (theta = 0.13; Z = 6.8), and BOLA DRBP1 and CYP21 (theta = 0.17; Z = 10.4). These results suggest an order BOLA DRBP1-PRL-CYP21, although in a multilocus analysis the alternative order PRL-BOLA DRBP1-CYP21 was also possible. The data confirm and extend the previously established syntenic relationship between these markers on bovine chromosome 23 and provide points of anchorage for further linkage studies in the reference pedigrees described.

Animals↗
PubMed1990

The bovine genome contains polymorphic microsatellites.

Dinucleotide repeats constitute so-called microsatellites of the human and other eukaryotic genomes. Microsatellite polymorphisms can be identified through the amplification of the microsatellite DNA using the polymerase chain reaction (PCR), followed by resolution of the amplified DNA fragments on a polyacrylamide sequencing gel. We performed a preliminary sequence database search to identify bovine sequences containing (CA)n, (AC)n, (GT)n, or (TG)n blocks, with n greater than or equal to 6. This search yielded 10 sequences containing one or two of the specified repeat blocks and often additional dinucleotide repeat blocks. One of the microsatellite-containing regions has been sequenced twice from independent clones and the reported sequences showed variation in the number of repeats. PCR-amplified fragments of another sequence, the gene for steroid 21-hydroxylase, ranged from 186 to 216 nucleotides in 43 unrelated animals. The database search, as well as the hypervariable microsatellite in the bovine steroid 21-hydroxylase gene, indicates that dinucleotide blocks may be an abundant source of DNA polymorphism in cattle.

Animals↗