Localization of the human erbB-2 gene on normal and rearranged chromosomes 17 to bands q12-21.32

Through the use of a cDNA probe, the human erbB-2 gene was localized by in situ hybridization of normal human chromosomes at 17q11-q21. In situ hybridization of chromosomes derived from fibroblasts carrying a constitutional 15;17t(q22.3;q11.21) translocation showed that the erbB-2 gene was relocated on the rearranged chromosome 15. These results as well as grain localization on prophase chromosomes locate the erbB-2 gene at 17q12-q21.32. This localization may facilitate the search for human malignancies with chromosome changes involving the erbB-2 gene.     

Regional mapping of the human gene encoding the novel pituitary polypeptide 7B2 to chromosome 15q13----q14 by in situ hybridization

Genetic sequences encoding the novel pituitary polypeptide 7B2 were isolated from a human pituitary cDNA library. Hybridization analysis of a panel of human x mouse cell hybrids with a 7B2 cDNA probe indicated that the locus for the human 7B2 gene is probably located on chromosome 15. In situ hybridization analysis of metaphase chromosomes allowed the regional localization of the 7B2 gene to chromosome 15 at q13----q14.     

Isolation and subregional mapping of an arbitrary cloned probe detecting a common RFLP on human chromosome 2.

In the course of studies on restriction fragment length polymorphisms (RFLPs) being conducted in our laboratory, several single-copy cloned probes have been generated from specific human chromosomes using murine-human hybrid cell libraries. The following describes the isolation and subregional localization of an arbitrary single-copy cloned probe for human chromosome 2. This probe, designated pXG-18, has detected a common TaqI polymorphism in addition to two other RFLPs using the restriction enzymes MspI and HindIII. This sequence maps to the interval q32-q36 of chromosome 2, a region of the human genome to which very few markers have been assigned.     

Dual localization of the human gene encoding hnRNP I/PTB protein to chromosomes 19p13.3 and 14q23

A cDNA probe representative of the human hnRNP I/PTB gene was used to perform fluorescence in situ hybridization (FISH) on metaphases of human chromosomes. A new localization was found on band 19p13.3 in addition to the previously reported localization to band 14q23. Identical results were obtained when FISH analysis was repeated with probes covering different parts of the hnRNP I cDNA clone. This supported the notion that most, if not all, of the sequences of the different parts of this clone are present on both chromosomes. Moreover, Southern blot analysis of DNAs from interspecies somatic hybrids containing chromosomes 19 and 14 revealed that the whole hnRNP I cDNA probe generated very similar patterns in each hybrid DNA. These data suggest that two closely related copies of the hnRNP I gene exist in the human genome. Received: 19 January 1996 / Revised: 9 March 1996     

Chromosomal localization of the human proenkephalin and prodynorphin genes.

DNA probes derived from rat and human proenkephalin and prodynorphin genes have been used to localize these two opiate neuropeptide genes on human chromosomes. Hybridization of probes to Southern blots made with DNAs from a rodent-human somatic-cell hybrid panel indicates localization of proenkephalin to human chromosome 8 and of prodynorphin to human chromosome 20. In situ hybridization to metaphase chromosomes confirms these assignments and indicates regional localizations of proenkephalin to 8q23-q24 and of prodynorphin to 20p12-pter. A human genomic prodynorphin clone reveals a frequent two-allele TaqI polymorphism.     

Localization of the single copy gene Mdh2 on Xenopus tropicalis chromosomes by FISH-TSA

A single copy gene, mitochondrial malate dehydrogenase 2 (Mdh2), was localized on Xenopus tropicalis chromosomes by fluorescence in situ hybridization coupled with tyramide signal amplification (FISH-TSA). The respective cDNA was cloned and sequenced. The labeled probe hybridized with a subcentromeric region of the long arms of homologous chromosomes 3. Results of comparison of the gene localization with previously mapped X. laevis paralogs strongly suggest a common evolutionary origin of chromosomes 3 and 8 in X. laevis and chromosome 3 in X. tropicalis. This is the first time that a single copy gene has been visualized on X. tropicalis chromosomes. The FISH-TSA method gives a strong signal with a 1-kb labeled probe.     

Origin of human chromosome 2 revisited

Similarities in chromosome banding patterns and hornologies in DNA sequence between chromosomes of the great apes and humans have suggested that human chromosome 2 originated through the fusion of two ancestral ape chromosomes. A lot of work has been directed at understanding the nature and mechanism of this fusion. The recent availability of the human chrornosome-2-specific alpha satellite DNA probe D2Z and the human chromosome-2p-specific subtelomeric DNA probe D2S445 prompted us to attempt cross-hybridization with chromosomes of the chimpanzee (Pan troglodytes), gorilla (Gorilla gorilla) and orangutan (Pongo pygmaeus) to search for equivalent locations in the great apes and to comment on the origin of human chromosome 2. The probes gave different results. No hybridization to the chromosome-2-specific alpha satellite DNA probe was observed on the presumed homologous great ape chromosomes using both high-stringency and low-stringency post-hybridization washes, whereas the subtelomeric-DNA probe specific for chromosome 2p hybridized to telomeric sites of the short arm of chromosome 12 of all three great apes. These observations suggest an evolutionary difference in the number of alpha satellite DNA repeat units in the equivalent ape chromosomes presumably involved in the chromosome fusion. Nevertheless, complete conservation of DNA sequence of the subtelomeric repeat sequence D2S445 in the ape chromosomes is demonstrated.     

Isolation of a human laminin B2 (LAMB2) cDNA clone and assignment of the gene to chromosome region 1q25----q31

Laminin B2 is one of the three polypeptide chains of laminin, a large, complex glycoprotein synthesized by a variety of cells and specifically deposited in basement membranes. A cloned cDNA that encodes the human laminin B2 chain was isolated and characterized. The human laminin B2 gene (LAMB2) was assigned to region 1q25----q31 by (1) hybridization of the probe to DNA from a panel of human x mouse somatic cell hybrids containing different human chromosomes and (2) in situ hybridization to isolated metaphase chromosomes.     

Mapping of the gene encoding the multifunctional protein carrying out the first three steps of pyrimidine biosynthesis to human chromosome 2

Summary The CAD gene encodes a trifunctional protein that carries the activities of the first three enzymes (carbamyl phosphate synthetase II, aspartate transcarbamylase, and dihydroorotase) of de novo pyrimidine biosynthesis. Genomic fragments of the human CAD gene have been obtained by screening a human genomic library in bacteriophage lambda using a Syrian hamster cDNA clone as a probe. These human genomic clones have been used to assign the CAD gene to human chromosome 2 using in situ hybridization to human metaphase chromosomes and Southern blot hybridization analysis of DNA isolated from a panel of Chinese hamster/human hybrid cells. In situ hybridization analysis has allowed further localization of this gene to the chromosomal region 2p21-p22.     

The placental ribonuclease inhibitor (RNH) gene is located on chromosome subband 11p15.5

The ribonuclease inhibitor from human placenta is a tight-binding inhibitor of alkaline and neutral ribonucleases, including the blood vessel-inducing protein, angiogenin. The location of the inhibitor gene within the human genome has now been determined. Utilizing human-rodent hybrid cell lines, it was found on chromosome 11. The localization was refined to chromosome band 11p15 by in situ hybridization of the ribonuclease inhibitor cDNA to normal metaphase chromosomes. A further refinement was obtained by in situ hybridization of the probe to metaphase chromosomes from RPMI 8402 cells, a line containing a well-characterized translocation t(11;14)(p15;q11) with a chromosome 11 breakpoint between the insulin-like growth factor 2 (IGF2) and Harvey rat sarcoma viral oncogene homolog genes. This analysis has localized the ribonuclease inhibitor gene to chromosome subband 11p15.5, distal to the IGF2 gene.     

Assignment of the human pro alpha 2(I) collagen structural gene (COLIA2) to chromosome 7 by molecular hybridization.

A cDNA for the pro alpha 2 chain of human type I collagen has been recently cloned and amplified. We have used this specific probe to identify the human chromosome carrying the pro alpha 2(I) collagen gene. The DNA from 17 independent human/hamster and human/mouse somatic cell hybrids was digested by Eco RI and the restriction pattern analyzed in Southern blot experiments, using the 32P-labeled cDNA as a hybridization probe. The gene coding for the pro alpha 2 collagen subunit could be unambiguously assigned to human chromosome 7. All the other chromosomes, including chromosome 17, were excluded.     

Localization of the villin gene on human chromosome 2q35-q36 and on mouse chromosome 1

Summary A partial cDNA clone coding for the 110 carboxyterminal amino acids of human villin was used for mapping the human villin gene. In situ hybridization experiments on human chromosomes with tritiated probe allowed the regional localization of the villin locus to chromosome 2 at q35-36. Data obtained from restriction fragment length polymorphism analysis of two mouse species demonstrated the assignment of the villin gene to mouse chromosome 1 by assessment of linkage with the fast skeletal isoform of the myosin light-chain gene. These villin gene localizations add a fourth locus to the conserved gene cluster encoding the fast skeletal muscle isoform of the myosin light chain, isocitrate dehydrogenase, and the crystallins and confirm the partial homology of the human chromosome 2 long arm and mouse chromosome 1.     

Chromosomal mapping and nucleotide sequence of a human DNA autonomously replicating sequence

A 1.1-kb human DNA fragment (ARSH1) capable of functioning as a putative origin of replication in yeast cells has been characterized both by in situ hybridization to human metaphase chromosomes and by DNA sequencing. Our hybridization studies show a preferential localization of ARSH1 in chromosome regions 1p34-36 and 2q34-37. DNA sequence analysis indicates that in addition to the consensus sequence required for ARS function in yeast cells, nuclear matrix-associated DNA motifs are also present in the 1.1-kb fragment. These results suggest that ARSH1 sequences may serve as points of anchorage to the nuclear matrix for chromosomes 1 and 2.     

The Gene for Human Glutaredoxin (GLRX) Is Localized to Human Chromosome 5q14

Glutaredoxin is a small protein (12 kDa) catalyzing glutathione-dependent disulfide oxidoreduction reactions in a coupled system with NADPH, GSH, and glutathione reductase. A cDNA encoding the human glutaredoxin gene (HGMW-approved symbol GLRX) has recently been isolated and cloned from a human fetal spleen cDNA library. The screening of a human genomic library in Charon 4A led to the identification of three genomic clones. Using fluorescencein situhybridization to metaphase chromosomes with one genomic clone as a probe, the human glutaredoxin gene was localized to chromosomal region 5q14. This localization at chromosome 5 was in agreement with the somatic cell hybrid analysis, using DNA from a human–hamster and a human–mouse hybrid panel and using a human glutaredoxin cDNA as a probe.     

Molecular cytogenetic analysis of DNA from pericentric heterochromatin of chromosome 2L of malaria mosquito <Emphasis Type="Italic">Anopheles beklemishevi</Emphasis> (culicidae,Diptera)

Using the method of microdissection of polytene chromosomes, followed by in situ hybridization, chromosomal localization of region-specific DNA probe from pericentic heterochromatin of chromosome 2L of Anopheles beklemishevi Stegnii et Kabanova was examined on polytene chromosomes of Anopheles atroparvus van Thiel, An. messeae Fall, and An. beklemishevi. DNA sequences homologous to the probe used were found in all species examined on chromosomes 2 and 3 in pericentric regions and in attachment regions. The exclusion were the attachment regions of chromosome XL in An. beklemishevi and An. messeae, and pericentric region of arm 2R in An. messeae. Pericentric α -heterochromatin of arm 2L in An. messeae and arm 3R in An. atroparvus also contained no sequences homologous to the DNA probe. The data obtained were compared with the earlier obtained data on localization of species-specific probe from the segment of chromosome 2R of An. atroparvus on chromosomes of An. artoparvus, An. messeae, and An. beklemishevi. The differences between the species in the sites of probes localization and fluorescence intensity revealed pointed to the existence of individual sequence associations in the regions of chromosomes attachment.     

Chromosomal localization of a human myosin heavy-chain gene by in situ hybridization

Summary A cloned rabbit heart muscle myosin heavy-chain cDNA was hybridized in situ with human metaphase chromosomes. The probe was known to have sequence homology with human genomic heavy-chain DNA. Only one site in the human haploid karyotype was labeled with the cDNA, and this site was found on the short arm of chromosome 17. The localization of autoradiographic grains suggests a subregional assignment of the myosin heavy-chain locus to 17p 1,2-pter.     

Assignment of the human fast skeletal muscle myosin alkali light chains gene (MLC1F/MLC3F) to 2q 32.1-2qter

Summary A DNA probe derived from a mouse intronless pseudogene including coding regions for the myosin fast skeletal muscle alkali light chains, MLC1_F/MLC3_F (suggested HGM symbol, MYL1), was tested on a panel of 25 independent man-rodent somatic cell hybrids in order to assign the human MLC1_F/MLC3_F gene to a human chromosome. A 3.7-kb TaqI human fragment was found to correlate with the presence of chromosome 2 in the hybrids, characterized both by cytogenetic analysis and reference enzyme markers. A regional assignment to 2q32.1-qter was possible using hybrids whose human parental strains bore a reciprocal translocation t(X;2) (p22;q32.1). The fact that IDH1 and the MLC1_F/MLC3_F gene are closely linked on chromosome 1 in the mouse and map to the same region of human chromosome 2 in man indicates, that these chromosomes have a conserved region of homology between them and that the human 3.7-kb TaqI fragment corresponds indeed to a functional gene.     

HEP-2细胞染色体不稳定性与kinetochore变异

染色体非整倍性畸变是恶性肿瘤细胞的显著细胞遗传学特征,但其诱发染色体数目不稳定的机制一直尚未阐明。本研究从与染色体分离直接相关的动粒(kinetochore)角度,采用kine-tochore-NOR同步银染技术对HEP-2细胞染色体kinetochore变异进行分析,以探讨恶性肿瘤细胞染色体数目变异的形成机制。实验共分析HEP-2细胞分裂相308个,计染色体16 962条,正常对照个体外周血细胞分裂相300个,计染色体13 800条。结果表明:与正常人外周血细胞相比,HEP-2细胞染色体kinetochore缺失和kinetochore迟滞复制频率显著升高(P<0.01),而kinetochore-NOR融合频率二者没有显著差异(P>0.05),这些结果提示kinetochore缺失和kinetochore迟滞复制可能是HEP-2细胞染色体非整倍性变异起源的诱因之一。此外,我们还在某些HEP-2细胞染色体上观察到多重kinetochore现象,并认为染色体多重kinetochore可能是恶性肿瘤细胞染色体结构畸变产生的一个新的途径。     

Atomic force microscopy and scanning near-field optical microscopy studies on the characterization of human metaphase chromosomes

A better knowledge of biochemical and structural properties of human chromosomes is important for cytogenetic investigations and diagnostics. Fluorescence in situ hybridization (FISH) is a commonly used technique for the visualization of chromosomal details. Localizing specific gene probes by FISH combined with conventional fluorescence microscopy has reached its limit. Also, microdissecting DNA from G-banded human metaphase chromosomes by either a glass tip or by laser capture needs further improvement. By both atomic force microscopy (AFM) and scanning near-field optical microscopy (SNOM), local information from G-bands and chromosomal probes can be obtained. The final resolution allows a more precise localization compared to standard techniques, and the extraction of very small amounts of chromosomal DNA by the scanning probe is possible. Besides new strategies towards a better G-band and fluorescent probe detection, this study is focused on the combination of biochemical and nanomanipulation techniques which enable both nanodissection and nanoextraction of chromosomal DNA.     

The human lactase-phlorizin hydrolase gene is located on chromosome 2

The lactase-phlorizin hydrolase gene was assigned to chromosome 2 by analysis of Southern blots of DNA from a panel of human-rodent cell hybrids containing characteristic sets of human chromosomes. The hybridization probe used was a recently isolated cDNA clone of the human lactase-phlorizin hydrolase gene.