PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Contig Mapping”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

A dual-color FISH framework map for the characterization of the Sai1 tumor suppression region on rat chromosome 5.

The analysis of cell hybrids between malignant mouse hepatoma cells and normal rat fibroblasts has previously demonstrated the critical role of a deletion in rat chromosome 5 (RNO5) that was related to an anchorage independent phenotype. Those hybrids that were anchorage independent displayed loss of the entire RNO5 or an interstitial deletion in RNO5. These findings suggested that a putative tumor suppressor gene, Sai1 (suppression of anchorage independence 1), was located within the deleted region. To explore the molecular basis of the tumor suppressor activity of the Sai1 region, we analyzed the RNO5q23-q36 region with several genes and microsatellite markers that could be assigned to the region, as well as with new markers derived by representational difference analysis (RDA) or by microdissection. Dual-color FISH was used to construct a detailed physical map of the entire RNO5. These new data can be used to connect the physical and linkage maps in the rat, as well as to identify the details of the comparative map with other mammalian species including humans and mice. Using as FISH reagents genomic YAC, P1, or phage lambda clones corresponding to RNO5 markers, the order and unique positions of 18 markers could be established. The map provided a framework for the detailed characterization of the deletion found in anchorage independent hybrids. All markers within the bands RNO5q31.3-q35 were shown to be lost, including known cancer-related genes such as Ifna (5q32), Cdkn2a, -b (5q32), Jun (5q34), and Cdkn2c (5q35). However, the aberration in the deletion chromosome turned out to be more complex than originally thought in that we detected the presence of a paracentric inversion in addition to a deletion. The inversion led to the juxtaposition of the gene markers Tal2 (5q24.1) and Cd30lg (5q24.3). The framework map will provide the basis for the detailed physical YAC clone contig mapping of this region, and facilitate the identification and characterization of the Sai1 locus.

Animals↗

Interleukin-1 receptor cluster: gene organization of IL1R2, IL1R1, IL1RL2 (IL-1Rrp2), IL1RL1 (T1/ST2), and IL18R1 (IL-1Rrp) on human chromosome 2q.

The family of interleukin-1 receptor-like genes currently has six known members. We have constructed a contig of 10 overlapping human PAC clones that covers 530 kb and includes five of the six family members. The termini of the contig were mapped to the interval between D2S373 and D2S176 (chromosome 2q12) by radiation hybrid mapping. The contig contains the genes (cen --> tel), in the order given, for the type II interleukin-1 (IL-1) receptor (IL1R2), the type I IL-1 receptor (IL1R1), the IL-1 receptor-related protein 2 (IL1RL2), T1/ST2/fit-1 (IL1RL1), and the IL-1 receptor-related protein 1, which has recently been shown to be a component of the IL-18 receptor (IL18R1). We show that all the genes are transcribed in the same direction, with IL1R2 being transcribed toward the cluster. The only known family member that is absent from the human contig is the IL-1 receptor accessory protein gene (IL1RAP), which maps to 3q28.

Blotting, Southern↗

Additional complexity on human chromosome 15q: identification of a set of newly recognized duplicons (LCR15) on 15q11-q13, 15q24, and 15q26.

Several cytogenetic alterations affect the distal part of the long arm of human chromosome 15, including recurrent rearrangements between 12p13 and 15q25, which cause congenital fibrosarcoma (CFS). We present here the construction of a BAC/PAC contig map that spans 2 Mb from the neurotrophin-3 receptor (NTRK3) gene region on 15q25.3 to the proximal end of the Bloom's syndrome region on 15q26.1, and the identification of a set of new chromosome 15 duplicons. The contig reveals the existence of several regions of sequence similarity with other chromosomes (6q, 7p, and 12p) and with other 15q cytogenetic bands (15q11-q13 and 15q24). One region of similarity maps on 15q11-q13, close to the Prader-Willi/Angelman syndromes (PWS/AS) imprinting center. The 12p similar sequence maps on 12p13, at a distance to the ets variant 6 (ETV6) gene that is equivalent on 15q26.1 to the distance to the NTRK3 gene. These two genes are the targets of the CFS recurrent translocations, suggesting that misalignments between these two chromosomes regions could facilitate recombination. The most striking similarity identified is based on a low copy repeat sequence, mainly present on human chromosome 15 (LCR15), which could be considered a newly recognized duplicon. At least 10 copies of this duplicon are present on chromosome 15, mainly on 15q24 and 15q26. One copy is located close to a HERC2 sequence on the distal end of the PWS/AS region, three around the lysyl oxidase-like (LOXL1) gene on 15q24, and three on 15q26, one of which close to the IQ motif containing GTPase-activating protein 1 (IQGAP1) gene on 15q26.1. These LCR15 span between 13 and 22 kb and contain high identities with the golgin-like protein (GLP) and the SH3 domain-containing protein (SH3P18) gene sequences and have the characteristics of duplicons. Because duplicons flank chromosome regions that are rearranged in human genomic disorders, the LCR15 described here could represent new elements of rearrangements affecting different regions of human chromosome 15q.

Base Sequence↗

Genetic refinement and physical mapping of a chromosome 16q candidate region for inflammatory bowel disease.

Crohn's disease (CD) is a complex genetic disorder for which a susceptibility gene, IBD1, has been mapped within the pericentromeric region of chromosome 16. In order to refine the location of IBD1, 77 multiplex CD families were genotyped for 26 microsatellite markers evenly spaced by approximately 1 cM. Nonparametric linkage analyses exhibited a maximum NPL score of 3.49 (P=2.37x10(-4)) in a region centred by markers D16S3136, D16S3117 and D16S770. Simulation studies showed that the probability for IBD1 to be located in a 5 cM region around these markers was 70%. A 2.5 Mb YAC and BAC contig map spanning this genetic region on chromosome band 16q12 was built. TDT analyses demonstrated suggestive association between the 207 bp allele of D16S3136 (P<0.05) and a new biallellic marker hb27g11f-end (P=0.01). These markers were located in the hb27g11 and hb87b10 BAC clones from the contig. Taken together, the present results provide a crucial preliminary step before an exhaustive linkage disequilibrium mapping of putatively transcribed regions to identify IBD1.

Alleles↗

Novel genes mapping to the critical region of the 5q- syndrome.

The 5q- syndrome is a myelodysplastic syndrome with specific hematological features and a good prognosis. Using molecular mapping techniques, we have previously defined the critical region of gene loss of the 5q- chromosome in the 5q- syndrome as the approximately 5-Mb region at 5q31-q33 flanked by the genes for FGF1 and IL12B. This region is completely represented by a series of overlapping YACs, and we are currently generating a transcription map with the aim of identifying the tumor-suppressor gene associated with the development of the 5q- syndrome. In this study two techniques have been used: first, the screening of full-length cDNA libraries with radiolabeled YACs and second, the mapping of chromosome 5-specific expressed sequence tags (ESTs) to a YAC contig. A 1-Mb YAC contig encompassing the CSF1R gene has been used to screen a fetal brain cDNA library, and this has resulted in the identification of two genes comprising one known gene previously localized to the region (ADRB2) and one known gene previously unlocalized. Six of 135 chromosome 5-specific ESTs were localized by PCR screening to the YAC contig mapping to the critical region of the 5q- syndrome. IMAGE cDNA clones for each of the six ESTs have been obtained. These seven (excluding ADRB2) newly assigned cDNA clones were subjected to further analysis. The expression patterns of each of the cDNA clones have been established in a range of human tissues, including bone marrow. Six of seven cDNAs are expressed in human bone marrow. Six of seven cDNAs have no known homology to any deposited human sequences, and one (C29) is dihydropyrimidinase-related protein-3, a member of a novel gene family. Genomic localization and expression patterns would suggest that these newly assigned cDNAs represent potential candidate genes for the 5q- syndrome.

Chromosome Deletion↗

In situ hybridization mapping of human chromosome 16: evidence for a high frequency of repetitive DNA sequences.

Fluorescence in situ hybridization (FISH) provides a rapid approach to regional localization of overlapping clone sets (contigs) developed by various fingerprinting approaches. We have used 70 cosmid clones derived from 48 different contigs, part of the developing contig map of chromosome 16 (Stallings et al., 1990, 1992a), to cytogenetically map an estimated 8.6 million base pairs (Mbp) of chromosome 16 DNA (approximately 8-9% total coverage). Although the majority of cosmid contigs hybridized to single sites on chromosome 16, a significant fraction (23%) hybridized to multiple regions on chromosome 16; a subset of these also hybridized to other human chromosomes. In most instances, clones that mapped to multiple locations were found to contain low-abundance repetitive DNA sequences. The FISH data presented here, coupled with published mapping data from somatic cell hybrids (Callen et al., 1992), permits independent verification of the integrity of chromosome 16 cosmid contigs. The order of clones derived by FISH agrees closely with the cell hybrid mapping data and can be correlated with chromosome bands and specific chromosomal translocation breakpoints.

Chromosome Mapping↗

High-resolution cytogenetic mapping of the short arm of chromosome 1 with newly isolated 411 cosmid markers by fluorescence in situ hybridization: the precise order of 18 markers on 1p36.1 on prophase chromosomes and "stretched" DNAs.

A high-resolution cytogenetic map of the short arm of chromosome 1 with newly isolated 411 cosmid markers was constructed by fluorescence in situ hybridization (FISH). These markers were scattered throughout chromosome 1p, but they were preferentially concentrated on R-band dominant regions such as 1p36, 1p34, 1p32, 1p22, and 1p13. Among these markers, 197 were localized on chromosome band 1p36, a region frequently deleted in neuroblastoma. Of these, 18 were precisely ordered on 1p36.1 by multicolor FISH of prophase chromosomes and "stretched" DNAs as follows: 1pter-163-41-11-1-226-586-568-614-631-665-451-199-190-561-241-74-1 76-652-1cen. The high-density map of chromosome 1p constructed here can provide useful landmarks for constructing a contig map of the short arm of chromosome 1 with YACs and cosmid clones and will expedite the identification of breakpoints and/or tumor suppressor gene(s) associated with several types of malignant tumors that frequently exhibit chromosomal aberrations or deletions of chromosome 1p.

Animals↗

Male mouse recombination maps for each autosome identified by chromosome painting.

Linkage maps constructed from genetic analysis of gene order and crossover frequency provide few clues to the basis of genomewide distribution of meiotic recombination, such as chromosome structure, that influences meiotic recombination. To bridge this gap, we have generated the first cytological recombination map that identifies individual autosomes in the male mouse. We prepared meiotic chromosome (synaptonemal complex [SC]) spreads from 110 mouse spermatocytes, identified each autosome by multicolor fluorescence in situ hybridization of chromosome-specific DNA libraries, and mapped >2,000 sites of recombination along individual autosomes, using immunolocalization of MLH1, a mismatch repair protein that marks crossover sites. We show that SC length is strongly correlated with crossover frequency and distribution. Although the length of most SCs corresponds to that predicted from their mitotic chromosome length rank, several SCs are longer or shorter than expected, with corresponding increases and decreases in MLH1 frequency. Although all bivalents share certain general recombination features, such as few crossovers near the centromeres and a high rate of distal recombination, individual bivalents have unique patterns of crossover distribution along their length. In addition to SC length, other, as-yet-unidentified, factors influence crossover distribution leading to hot regions on individual chromosomes, with recombination frequencies as much as six times higher than average, as well as cold spots with no recombination. By reprobing the SC spreads with genetically mapped BACs, we demonstrate a robust strategy for integrating genetic linkage and physical contig maps with mitotic and meiotic chromosome structure.

Adaptor Proteins, Signal Transducing↗

A high-resolution radiation hybrid map of chicken chromosome 5 and comparison with human chromosomes.

BACKGROUND: The resolution of radiation hybrid (RH) maps is intermediate between that of the genetic and BAC (Bacterial Artificial Chromosome) contig maps. Moreover, once framework RH maps of a genome have been constructed, a quick location of markers by simple PCR on the RH panel is possible. The chicken ChickRH6 panel recently produced was used here to construct a high resolution RH map of chicken GGA5. To confirm the validity of the map and to provide valuable comparative mapping information, both markers from the genetic map and a high number of ESTs (Expressed Sequence Tags) were used. Finally, this RH map was used for testing the accuracy of the chicken genome assembly for chromosome 5. RESULTS: A total of 169 markers (21 microsatellites and 148 ESTs) were typed on the ChickRH6 RH panel, of which 134 were assigned to GGA5. The final map is composed of 73 framework markers extending over a 1315.6 cR distance. The remaining 61 markers were placed alongside the framework markers within confidence intervals. CONCLUSION: The high resolution framework map obtained in this study has markers covering the entire chicken chromosome 5 and reveals the existence of a high number of rearrangements when compared to the human genome. Only two discrepancies were observed in relation to the sequence assembly recently reported for this chromosome.

Animals↗

High-resolution cytogenetic mapping of 342 new cosmid markers including 43 RFLP markers on human chromosome 17 by fluorescence in situ hybridization.

We have constructed a high-resolution cytogenetic map of human chromosome 17 with 342 cosmid markers, each newly isolated from a cosmid library constructed from a human-mouse hybrid cell line containing a single human chromosome 17. Direct mapping on R- and/or G-banded (pro)metaphase chromosomes by fluorescence in situ hybridization localized these markers throughout the chromosome, although density was highest in the R-band-dominant regions of 17p13, 17p11.2, 17q11.2-q12, 17q21.3, 17q23, and 17q25. By screening some of the cosmid clones, we identified 71 polymorphic systems with 43 markers; 11 of these are VNTRs. As our high-resolution cytogenetic map contains a large number of markers, it can provide useful landmarks for a contig map of chromosome 17. Furthermore, the map will contribute to positional cloning of aberrant genes responsible for inherited diseases such as Miller-Dieker syndrome (MDS), Smith-Magenis syndrome (SMS), and familial early-onset breast cancer, as well as putative tumor suppressor genes on this chromosome.

Animals↗

Mapping analysis of the Xylella fastidiosa genome.

A cosmid library was made of the 2.7 Mb genome of the Gram-negative plant pathogenic bacterium Xylella fastidiosa and analysed by hybridisation mapping. Clones taken from the library as well as genomic restriction fragments of rarely cutting enzymes were used as probes. The latter served as a backbone for ordering the initial map contigs and thus facilitated gap closure. Also, the co-linearity of the cosmid map, and thus the eventual sequence, could be confirmed by this process. A subset of the eventual clone coverage was distributed to the Brazilian X.FASTIDIOSA: sequencing network. Data from this effort confirmed more quantitatively initial results from the hybridisation mapping that the redundancy of clone coverage ranged between 0 and 45-fold across the genome, while the average was 15-fold by experimental design. Reasons for this not unexpected fluctuation and the actual gaps are being discussed, as is the use of this effect for functional studies.

Brazil↗

Characterization of four yeast artificial chromosome clones mapped to human chromosome 21q22.1 with eight markers.

Yeast artificial chromosome (YAC) clones have been successfully utilized to generate a YAC contig map of the long arm of human chromosome 21 (Hu21q). The chromosome subband of 21q22.1 where five genetic loci (IFNAR1, IFNAR2, CRFB4, AF-1, and GART) are mapped is a gene-rich region and needs to be characterized in further detail. YAC D142H8 and YAC F136C5, which were characterized previously by a functional YAC expression procedure, and two new YAC clones, YAC 872B5 and YAC 876D4 located at 21q22.1 whose YAC sizes are 800 kb and 1,500 kb, respectively, were used in this study. To obtain more markers useful for making a detailed physical map of the region, a purified yeast artificial chromosome (YAC D142H8) was used to screen the 3 x 1 S cDNA library. As a result three anonymous cDNA clones (Kmy1, Kmy2, and Qorf4) were obtained, and the nucleotide sequences of Kmy1 and Kmy2 were determined. In an attempt to make a detailed physical map of the region, the locations of five known genes as well as the three new markers were determined on the four YACs by Southern blot analysis. YAC 872B5 contained all markers except GART while YAC F136C5, YAC D142H8, and YAC 876D4 contained three markers (CRFB4, IFNAR1, and IFNAR2), four markers (Kmy1, Kmy2, Qorf4 and AF-1), and four markers (Kmy1, Kmy2, Qorf4 and GART), respectively. YAC 872B5 may represent 1,500 kb of the 21q22.1 subband and half of the 3 x 1 S region, so it should be very useful for studying the relevent region of the human chromosome functionally and physically.

Base Sequence↗

A 2.8-Mb clone contig of the multiple endocrine neoplasia type 1 (MEN1) region at 11q13.

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder that results in parathyroid, anterior pituitary, and pancreatic and duodenal endocrine tumors in affected individuals. The MEN1 locus is tightly linked to the marker PYGM on chromosome 11q13, and linkage analysis has placed the MEN1 gene within a 2-Mb interval flanked by D11S1883 and D11S449. As a step toward cloning the MEN1 gene, we have constructed a 2.8-Mb clone contig consisting of YAC and bacterial clones (PAC, BAC, and P1) for the D11S480 to D11S913 region. The bacterial clones alone represent nearly all of the 2.8-Mb contig. The contig was assembled based on a high-density STS-content analysis of 79 genomic clones (YAC, PAC, BAC, and P1) with 118 STSs. The STSs included 22 polymorphic markers and 20 transcripts, with the remainder primarily derived from the end sequences of the genomic clones. An independent cosmid contig for the 1-Mb PYGM-SEA region was also generated. Support for correctness of the 2.8-Mb contig map comes from an independent ordering of the clones by fiber-FISH. This sequence-ready contig will be a useful resource for positional cloning of MEN1 and other disease genes whose loci fall within this region.

Chromosomes, Artificial, Yeast↗

A physical map of chromosome 7 of Candida albicans.

As part of the ongoing Candida albicans Genome Project, we have constructed a complete sequence-tagged site contig map of chromosome 7, using a library of 3840 clones made in fosmids to promote the stability of repeated DNA. The map was constructed by hybridizing markers to the library, to a blot of the electrophoretic karyotype, and to a blot of the pulsed-field separation of the SfiI restriction fragments of the genome. The map includes 149 fosmids and was constructed using 79 markers, of which 34 were shown to be genes via determination of function or comparison of the DNA sequence to the public databases. Twenty-five of these genes were identified for the first time. The absolute position of several markers was determined using random breakage mapping. Each of the homologues of chromosome 7 is approximately 1 Mb long; the two differ by about 20 kb. Each contains two major repeat sequences, oriented so that they form an inverted repeat separated by 370 kb of unique DNA. The repeated sequence CARE2/Rel2 is a subtelomeric repeat on chromosome 7 and possibly on the other chromosomes as well. Genes located on chromosome 7 in Candida are found on 12 different chromosomes in Saccharomyces cerevisiae.

Candida albicans↗

Seeding of YACs over regions 1q41-q42.3 and 11q14.3-q23 with microdissection clones.

We describe the use of pooled, region-specific hybridisation probes to screen high-density replica filters of a human genome YAC library. The probes were derived by microdissection of an approximately 30-Mbp region subtending the translocation breakpoint on a der(1)(1;11)(q42.1;q14.3) chromosome. Of 70 microdissection clones used in pools of 4-10, 47 identified a total of 77 YAC recombinants, representing over 50% of the microdissected region. This strategy can easily be adapted to other poorly mapped subchromosomal regions of the human or other mammalian genomes and will provide a solid framework for detailed contig map constructions.

Chromosomes, Artificial, Yeast↗

Construction of two YAC contigs in human Xp11.23-p11.22, one encompassing the loci OATL1, GATA, TFE3, and SYP, the other linking DXS255 to DXS146.

We have constructed two YAC contigs in the Xp11.23-p11.22 interval of the human X chromosome, a region that was previously poorly characterized. One contig, of at least 1.4 Mb, links the pseudogene OATL1 to the genes GATA1, TFE3, and SYP and also contains loci implicated in Wiskott-Aldrich syndrome and synovial sarcoma. A second contig, mapping proximal to the first, is estimated to be over 2.1 Mb and links the hypervariable locus DXS255 to DXS146, and also contains a chloride channel gene that is responsible for hereditary nephrolithiasis. We have used plasmid rescue, inverse PCR, and Alu-PCR to generate 20 novel markers from this region, 1 of which is polymorphic, and have positioned these relative to one another on the basis of YAC analysis. The order of previously known markers within our contigs, Xpter-OATL1-GATA-TFE3-SYP-DXS255146- Xcen, agrees with genomic pulsed-field maps of the region. In addition, we have constructed a rare-cutter restriction map for a 710-kb region of the DXS255-DXS146 contig and have identified three CPG islands. These contigs and new markers will provide a useful resource for more detailed analysis of Xp11.23-p11.22, a region implicated in several genetic diseases.

Animals↗

[Radiation mapping as one of main methods of creating high resolution maps of human and animal genomes].

Radiation hybrid mapping (RH mapping) is considered as one of the main methods of constructing physical maps of mammalian genomes. In introduction, theoretical prerequisites of developing of the RH mapping and statistical methods of data analysis are discussed. Comparative characteristics of universal commercial panels of the radiation hybrid somatic cells (RH panels) are shown. In experimental part of the work, RH mapping is used to localise nucleotide sequences adjacent to NotI sites of human chromosome 3 with the aim to integrate contig map of NotI clones to comprehensive maps of human genome. Five nucleotide sequences adjacent to the sites of integration of papilloma virus in human genome and expressed in the cells of cervical cancer were localised. It was demonstrated that the region 13q14.3-q21.1 was enriched with nucleotide sequences involved in the processes of oncogenesis. RH mapping can be considered as one of the most perspective applications of the modern radiation biology in the field of molecular genetics, that is, in constructing physical maps of mammalian genomes with high resolution level.

Animals↗

Comparative mapping of human Chromosome 19 with the chicken shows conserved synteny and gives an insight into chromosomal evolution.

Human Chromosome 19 (HSA19) is virtually completely sequenced. A complete physical contig map made up of BACs and cosmids is also available for this chromosome. It is, therefore, a rich source of information that we have used as the basis for a comparative mapping study with the chicken. Various orthologs of genes known to map to HSA19 have been mapped in the chicken. Five chicken microchromosomes (two of which were previously undefined) are seen to show conserved synteny with this chromosome, along with individual gene homologs on Chr 1 and another tiny microchromosome. Compared with the mouse, which has 12 chromosomal regions homologous to HSA19, the chicken genotype displays fewer evolutionary rearrangements. The ancestral nature of the chicken karyotype is demonstrated and may prove to be an excellent tool for studying genome evolution.

Animals↗