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A Vignal

Publications and source records attributed to A Vignal.

At least 37 records · Page 2Linked to original sources
PubMed2000

A consensus linkage map of the chicken genome.

A consensus linkage map has been developed in the chicken that combines all of the genotyping data from the three available chicken mapping populations. Genotyping data were contributed by the laboratories that have been using the East Lansing and Compton reference populations and from the Animal Breeding and Genetics Group of the Wageningen University using the Wageningen/Euribrid population. The resulting linkage map of the chicken genome contains 1889 loci. A framework map is presented that contains 480 loci ordered on 50 linkage groups. Framework loci are defined as loci whose order relative to one another is supported by odds greater then 3. The possible positions of the remaining 1409 loci are indicated relative to these framework loci. The total map spans 3800 cM, which is considerably larger than previous estimates for the chicken genome. Furthermore, although the physical size of the chicken genome is threefold smaller then that of mammals, its genetic map is comparable in size to that of most mammals. The map contains 350 markers within expressed sequences, 235 of which represent identified genes or sequences that have significant sequence identity to known genes. This improves the contribution of the chicken linkage map to comparative gene mapping considerably and clearly shows the conservation of large syntenic regions between the human and chicken genomes. The compact physical size of the chicken genome, combined with the large size of its genetic map and the observed degree of conserved synteny, makes the chicken a valuable model organism in the genomics as well as the postgenomics era. The linkage maps, the two-point lod scores, and additional information about the loci are available at web sites in Wageningen (http://www.zod.wau.nl/vf/ research/chicken/frame_chicken.html) and East Lansing (http://poultry.mph.msu.edu/).

Animals↗
PubMed1998

Mapping of FASN and ACACA on two chicken microchromosomes disrupts the human 17q syntenic group well conserved in mammals.

Fatty acid synthase and Acetyl-CoA carboxylase are both key enzymes of lipogenesis and may play a crucial role in the weight variability of abdominal adipose tissue in the growing chicken. They are encoded by the FASN and ACACA genes, located on human Chromosome (Chr) 17q25 and on Chr 17q12 or 17q21 respectively, a large region of conserved synteny among mammals. We have localized the homologous chicken genes FASN and ACACA coding for these enzymes, by single-strand conformation polymorphism analysis on different linkage groups of the Compton and East Lansing consensus genetic maps and by FISH on two different chicken microchromosomes. Although synteny is not conserved between these two genes, our results revealed linkage in chicken between FASN and NDPK (nucleoside diphosphate kinase), a homolog to the human NME1 and NME2 genes (non-metastatic cell proteins 1 and 2), both located on human Chr 17q21.3, and also between FASN and H3F3B (H3 histone family 3B), located on human Chr 17q25. The analysis of mapping data from the literature for other chicken and mammalian genes indicates rearrangements have occurred in this region in the mammalian lineage since the mammalian and avian radiation.

Acetyl-CoA Carboxylase↗
PubMed1998

Identification of 16 chicken microchromosomes by molecular markers using two-colour fluorescence in situ hybridization (FISH).

A feature of avian karyotypes is the presence of microchromosomes. As a typical avian genome, the chicken karyotype (2n = 78) consists of nine pairs of macrochromosomes, including the W and Z sexual chromosomes, and 30 pairs of indistinguishable microchromosomes usually ordered arbitrarily by decreasing size. Despite their reduced size, microchromosomes represent one-third of the genome and have a high gene density. So as to provide a tool to identify them, we developed a set of large insert-containing clones to be used as tags in two-colour fluorescence in situ hybridization experiments. Seventeen clones, six of which contain a microsatellite sequence and two others the fatty acid synthase gene or genes from the major histocompatibility complex, all presenting a strong hybridization signal, were selected for this purpose and enabled us to identify 16 different microchromosomes. The ability to recognize individual microchromosomes will be of great value for cytogenetic gene mapping, assignation of linkage groups from genetic maps and other studies on avian genome structure.

Animals↗
PubMed1998

Integration of chicken cytogenetic and genetic maps: 18 new polymorphic markers isolated from BAC and PAC clones.

As an approach to integrate the chicken genetic and cytogenetic maps, bacterial artificial chromosome (BAC) and P1-derived artificial chromosome (PAC) clones were localized by fluorescence in situ hybridization (FISH) on chromosomes and by genetic mapping on the East Lansing and Compton reference families. Some of the clones used in this study were previously selected for the presence of potentially polymorphic (CA)n repeats and a microsatellite marker was developed when possible for genetic mapping. For other clones, a single strand conformational polymorphism (SSCP) was developed and used for this purpose. Between the two approaches, 18 markers linking the cytogenetic and genetic maps, seven on macrochromosomes and 11 on microchromosomes, were generated. Our results enabled the assignment and orientation of a linkage group to chromosome 3, together with the assignment of linkage groups to eight different microchromosomes, a fraction of the genome lacking mapping data and for which the degree of coverage by the genetic map was not well estimated previously.

Animals↗
PubMed1996

A comprehensive genetic map of the human genome based on 5,264 microsatellites.

The great increase in successful linkage studies in a number of higher eukaryotes during recent years has essentially resulted from major improvements in reference genetic linkage maps, which at present consist of short tandem repeat polymorphisms of simple sequences or microsatellites. We report here the last version of the Généthon human linkage map. This map consists of 5,264 short tandem (AC/TG)n repeat polymorphisms with a mean heterozygosity of 70%. The map spans a sex-averaged genetic distance of 3,699 cM and comprises 2,335 positions, of which 2,032 could be ordered with an odds ratio of at least 1,000:1 against alternative orders. The average interval size is 1.6 cM; 59% of the map is covered by intervals of 2 cM at most and 1% remains in intervals above 10 cM.

Algorithms↗
PubMed1996

Genotyping Procedures in Linkage Mapping

Genotyping methods based on nonradioactive detection of PCR products and suitable for large-scale mapping projects are described. Two alternative techniques are proposed for the genotyping of polymorphic short tandem repeats or microsatellite markers. The first is designed for investigators who do not have access to automatic sequencing machines. This technique uses multiplex analysis of PCR products that are separated on sequencing gels, transferred to nylon membranes, and detected by hybridization with nonradioactive probes. The second technique uses automatic sequencing machines for the detection of fluorescently labeled PCR products. Another method describes the analysis of nonpolymorphic markers in whole-genome radiation hybrids. This method uses separation and detection of PCR products on agarose gels.

Journal Article↗
PubMed1996

Mapping of the genetically independent chicken major histocompatibility complexes B@ and RFP-Y@ to the same microchromosome by two-color fluorescent in situ hybridization.

The chicken MHC is organized in two genetically independent gene complexes B@ and RFP-Y@. Previous studies have shown the localization of the B@ complex on a small microchromosome. By using two-color fluorescent in situ hybridization, we demonstrate the localization of the RFP-Y@ complex to the same chromosome. A recombination hot spot between the two loci might account for their independent segregation.

Animals↗
PubMed1995

Physical mapping of 30 CA repeats on human chromosome 22.

We report the physical mapping of 30 microsatellite markers specific for chromosome 22 by PCR amplification of DNA from hybrids that divide the long arm into 27 subregions. This work permits further refining of the genetic linkage ordering previously published.

Base Sequence↗
PubMed1995

Assignment of microsatellite sequences to the region duplicated in CMT1A (17p12): a useful tool for diagnosis.

Charcot-Marie-Tooth disease type 1A (CMT1A), the most prevalent form of the peripheral hereditary neuropathies, has been associated with a duplication of a genomic segment of 1.5 Mb, located in 17p11.2. Recently, the same segment has been found to be deleted in patients with another peripheral neuropathy, hereditary neuropathy with liability to pressure palsies (HNPP). Highly polymorphic markers are rare in this area, rendering the diagnosis highly dependent either on invasive examinations (like nerve biopsy) or not totally reliable (like gene dosage). Thus, we used a contig of YACs, including the whole region duplicated in CMT1A, to map highly polymorphic microsatellite loci, designed in Genethon. We showed that four of these loci are located in the duplicated region, allowing us to propose them as diagnostic markers for CMT1A and HNPP.

Charcot-Marie-Tooth Disease↗
PubMed1994

Apparent genetic homogeneity of the Treacher Collins-Franceschetti syndrome.

The Treacher Collins-Franceschetti syndrome (TCOF) or mandibulofacial dysostosis (MFD) is an autosomal dominant disorder characterized by craniofacial abnormalities and hearing loss. A refined genetic linkage map of the TCOF locus was established in 8 independent families, using 12 microsatellite DNA markers of the distal 5q. Positive lod score values were obtained for all markers with a maximum at the D5S413 locus (Zmax = 3.79 at theta = 0%). Multipoint linkage analysis and haplotype analysis supported the location of the gene between loci D5S434 and D5S412. These results are consistent with previous linkage analyses [Dixon et al.: Am J Hum Genet 49:17-22, 1991, Am J Hum Genet 52:907-914, 1993; Jabs et al.: Genomics 11:193-198, 1991, Genomics 18:7-13, 1993] and provide further evidence of genetic homogeneity in this syndrome.

Chromosomes, Human, Pair 5↗