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J Gellin

Publications and source records attributed to J Gellin.

At least 37 records · Page 2Linked to original sources
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↗
PubMed1998

Construction of a whole-genome radiation hybrid panel for high-resolution gene mapping in pigs.

We have developed a panel of 152 whole-genome radiation hybrids by fusing irradiated diploid pig lymphocytes or fibroblasts with recipient hamster permanent cells. The number and size of the porcine chromosome fragments retained in each hybrid clone were checked by fluorescence in situ hybridization with a SINE probe or by primed in situ labeling (PRINS) with SINE-specific primers. A strategy based on the interspersed repetitive sequence polymerase chain reaction (IRS-PCR) was developed for selected clones to determine if the large fragments painted by the SINE probe corresponded to one pig chromosome or to different fragments of several chromosomes. This strategy was buttressed by a double PRINS approach using primers specific for alpha-satellite sequences of two different groups of swine chromosomes. Genome retention frequency was estimated for each clone by PCR with 32 markers localized on different porcine chromosomes. Of the 152 hybrids produced, 126 were selected on the basis of cytogenetic content and chromosome retention frequency to construct a radiation hybrid map of swine chromosome 8. Our initial results for this chromosome indicate that the resolution of the radiation hybrid map is 18 times higher than that obtained by linkage analysis.

Animals↗
PubMed1997

Contribution to the physically anchored linkage map of the pig.

Thirty-three microsatellites have been mapped on the PiGMaP porcine genetic map. By comparison with the previously published PiGMaP maps, the maps of chromosome 2 (140 cM/70 cM) and chromosome 3 (180 cM/110 cM) were extended and new markers were mapped on the p-arm extremity of chromosome 7 and on the centromeric extremity of chromosome 15. New orders are proposed for markers on chromosomes 3 and 17. Six microsatellites isolated from cosmids were also localized on the cytogenetic map by fluorescent in situ hybridization. We tested the subcloning ligation mixture-polymerase chain reaction (SLiM-PCR) method for isolating microsatellites from cosmids. Subcloning is more effective when the cosmid harbours several microsatellites whereas SLiM-PCR is more straightforward when the cosmid contains a single microsatellite. Fifteen anonymous microsatellites were regionally assigned by using a hybrid cell panel. For map integration, the determination of a regional assignment of anonymous microsatellites by using a hybrid cell panel offers an alternative to microsatellite isolation from cosmids and their localizations by in situ hybridization.

Animals↗
PubMed1997

Mapping in pig of genes involved in sexual differentiation: AMH, WT1, FTZF1, SOX2, SOX9, AHC, and placental and embryonic CYP19.

Intersexuality has been reported in pigs and investigations are in progress to identify and physically map the genes involved in sex-reversal. In this study we have mapped on porcine chromosomes seven genes which might be implicated in this developmental pathway. Four genes were mapped by radioactive in situ hybridization: AMH (Anti-Müllerian Hormone) and WT1 (Wilms' Tumor gene 1) were both mapped to pig chromosome 2 (SSC2) in the q14-->q21 and p14-->q11 regions, placental CYP19 (cytochrome P450, subfamily XIX) and FTZF1 (fushi tarazu factor [Drosophila] homolog 1, alias SF1 [steroidogenic factor 1]) to pig chromosome 1 (SSC1) in the q14-->q17 and q210-->q211 regions respectively. Four other genes were regionally located by PCR analysis on a cytogenetically characterized porcine somatic cell hybrid panel: a second CYP19 gene (expressed in embryo) was mapped to porcine 1q12-->q17, AHC (alias DAX1, adrenal hypoplasia congenital) to porcine Xp24, SOX2 and SOX9 (SRY sex determining region Y-box 2 and 9) to 13q23-->q41 and 12p13-->p11 respectively. These results are in global agreement with mapping data available in other mammalian species.

Animals↗
PubMed1996

Human and porcine correspondence of chromosome segments using bidirectional chromosome painting.

The aim of this study was to determine the correspondence between human and porcine chromosome fragments using whole chromosome painting probes from both species in heterologous hybridization experiments (bidirectional heterologous chromosome painting). Bidirectional experiments allow the determination of segment-to-segment homologies between the chromosomes of these two species. Chromosome-specific painting probes from both species were, except one, obtained by DOP-PCR or PARM-PCR amplification of flow-sorted chromosomes. The probes labeled 95% of the total length of the porcine chromosomes with human painting probes and 60% of the human chromosomes in the reverse experiments. Syntenic relationships of chromosomal segments on the karyotype of both species were determined. There was close agreement between com- parative gene mapping data and the identified homologous segments; this comparison enabled orientation of the segments. We demonstrate that bidirectional heterologous chromosome painting is a highly efficient way of generating comparative cytogenetic maps.

Animals↗
PubMed1996

Accurate mapping of the "acid meat" RN gene on genetic and physical maps of pig chromosome 15.

It has been shown that a major gene, called RN, is responsible for the RTN technological yield, a meat quality porcine trait. Experimental families informative for the segregation of RN gene were constituted from animals belonging to the Laconie composite line. We have previously mapped the RN gene to Chromosome (Chr) 15 (Milan et al. Genet. Sel. Evol. 27, 195-199, 1995). A Chr 15 map was established with 16 markers. The RN gene was found to be located between markers Sw120 and Sw936, at 2 cM from Sw936 (LOD = 38.1). In addition, by localizing Sw936 at 15q21-22 using DISC-PCR, we also located RN on the physical map.

Animals↗
PubMed1996

Chromosomal localization of homeobox genes and associated markers on porcine chromosomes 3, 5, 12, 15, 16 and 18: comparative mapping study with human and mouse.

Four homeobox genes that belong to the four homeobox gene clusters known in mammals have been regionally assigned to four distinct porcine chromosomes in conserved regions between human and pig. HOXA11, HOXB6, HOXC8, and HOXD4 genes were mapped by radioactive in situ hybridization to porcine Chromosomes (Chrs) 18q21-24 (with a secondary signal in 16q14-21), 12p11-12, 5p11-12, and 15q22-23 respectively. Besides, we have also revealed the presence of a porcine homeobox (pig Hbx24) which, although showing DNA sequence homology with a mouse gene of HOXB cluster, was located on porcine Chr 3 (3p14-13) outside the Hox clusters. To support the identity of the homeobox gene clusters analyzed and in the light of the high sequence similarity among homeobox genes, we also localized markers known to be mapped near each Hox cluster in human. In this way, four genes were also mapped in pig: GAPD (5q12-21), GAD1 (15q21-22), INHBA (18q24), and IGFBP3 (18q24). Mapping of HOXA11, INHBA, and IGFBP3 on pig Chr 18 constitutes the first assignments of genes on this small chromosome. These new localizations extend the information on the conservation of four human chromosomal regions in the pig genome.

Animals↗
PubMed1996

Homologous and heterologous FISH painting with PARM-PCR chromosome-specific probes in mammals.

Numerous loci can be amplified by PARM-PCR on 300 sorted chromosomes in low-stringency conditions (annealing at 30 degrees C during the two first cycles) to produce a probe that can be used in FISH painting experiments. We demonstrate that, depending on the primer chosen for the amplification, patterns of different quality can be obtained. In order to design a primer that allows amplification of coding sequences, we have shown that motifs of at least seven glutamic acid repeats (GAG or GAA codons) are present in human proteins more frequently than expected. Moreover, these repeats do not correspond to triplet expansion and can be conserved between species. Using probes prepared from sorted chromosomes with (GAG)7 primer, we were able to achieve homologous FISH painting on human, porcine, ovine, and bovine species, and bidirectional heterologous FISH painting between human and porcine species. As an example, using probes for human Chromosome (Chr) 19 and porcine Chrs 1 and 6, we clearly defined the regional homologies existing between those chromosomes.

Animals↗
PubMed1996

Porcine linkage and cytogenetic maps integrated by regional mapping of 100 microsatellites on somatic cell hybrid panel.

Recently two main genetic maps [Rohrer et al. Genetics 136, 231 (1994); Archibald et al. Mamm. Genome 6, 157 (1995)] and a cytogenetic map [Yerle et al. Mamm. Genome 6, 175 (1995)] for the porcine genome were reported. As only a very few micro-satellites are located on the cytogenetic map, it appears to be important to increase the relationships between the genetic and cytogenetic maps. This document describes the regional mapping of 100 genetic markers with a somatic cell hybrid panel. Among the markers, 91 correspond to new localizations. Our study enabled the localization of 14 new markers found on both maps, of 54 found on the USDA map, and of 23 found on the PiGMaP map. Now 21% and 43% of the markers on the USDA and PiGMaP linkage maps respectively are physically mapped. This new cytogenetic information was then integrated within the framework of each genetic map. The cytogenetic orientation of the USDA linkage maps for Chromosomes (Chrs) 3, 8, 9, and 16 and of PiGMaP for Chr 8 was determined. USDA and PiGMaP linkage maps are now oriented for all chromosomes, except for Chrs 17 and 18. Moreover, the linkage group "R" from the USDA linkage map was assigned to Chr 6.

Animals↗
PubMed1996

Porcine alpha-1-antitrypsin (PI): cDNA sequence, polymorphism and assignment to chromosome 7q2.4- > q2.6.

A cDNA clone encoding the complete coding sequence for porcine alpha-1-antitrypsin (or alpha 1-protease inhibitor, PI) was isolated and its DNA sequence determined. The cDNA is assumed to encode alpha-1-antitrypsin on the basis of its sequence similarity to the corresponding cDNAs for human, baboon, rat, mouse, sheep and cow. The porcine cDNA clone was used in conjunction with BamHI, KpnI, MspI, SacI, TaqI and XbaI to develop restriction fragment length polymorphism-based genetic markers for linkage mapping in pigs. The cDNA has also been used to map the porcine PI locus to chromosome 7q2.4- > q2.6 by radioactive in situ hybridization. Thus, the PI locus has been added to the developing physical and genetic maps of the porcine genome.

Animals↗