Assignment of 12 loci to rat chromosome 5: evidence that this chromosome is homologous to mouse chromosome 4 and to human chromosomes 9 and 1 (1p arm)

Twelve loci have been assigned to rat chromosome 5: aldolase B (ALDOB), atrial natriuretic factor (ANF = pronatriodilatin, PND), D4RP1, DSI1, galactosyltransferase (GGTB2), glucose transporter (GLUT1), interferon alpha 1 and related interferon alpha (INFA), interferon beta (INFB), lymphocyte-specific protein-tyrosine kinase (LCK), oncogene MOS, alpha 2U-globulin (major urinary protein, MUP), and orosomucoid (ORM, also called alpha 1-acid glycoprotein, AGP). Among these, the interferon alpha and beta genes map in the q22-23 region, which also contains a transformation suppressor gene (SAI1). The other loci reside outside this region. This study also indicated that the rat genome contains 2 LCK genes, unlike the human and murine genomes. These new assignments on rat chromosome 5 demonstrate that this chromosome is highly homologous to mouse chromosome 4 and carries synteny groups conserved on human chromosome 9 (interferon alpha and beta, galactosyltransferase, orosomucoid, and aldolase B genes) and on the short arm of human chromosome 1 (MYCL, glucose transporter, protein kinase LCK, and atrial natriuretic factor genes).     

Four human Chromosome 3q and four human Chromosome 21 loci map onto sheep Chromosome 1q

Eight new loci have been assigned to sheep Chromosome (Chr) 1q by use of a chromosomally characterized minipanel of sheep x hamster cell hybrids. Four loci, which have been mapped to the distal region of human Chr 3q, are ceruloplasmin (CP), sucrase isomaltase (SI), glucose transporter 2 (GLUT2), and ectopic viral integration site 1 (EVI1). The other four loci, on human Chr 21, include interferon alpha receptor (IFNAR); interferon inducible protein p78, murine (MX1); collagen type VI, alpha 1 (COL6A1); and S100 protein, beta polypeptide (S100B). All of these loci, except GLUT2 and MX1, have been mapped onto bovine Chr 1 or are syntenic with loci on this chromosome. The in situ localization of transferrin (TF) to sheep Chr 1q42-q45 confirms our previous assignment of this locus and independently anchors the eight new syntenic loci to sheep Chr 1q.     

Localisation of neurone-specific enolase (ENO2) to 12p13

We have localised the human cDNA for neurone-specific enolase (ENO2) to chromosome region 12p13 by in situ hybridisation. Two additional smaller peaks of hybridisation to specific chromosomal subregions were observed. That on chromosome 1p36 probably represents cross-hybridisation to the locus for nonneuronal enolase (ENO1), which has been previously localised to this chromosome and with which ENO2 shares homology. A further gene for a member of the enolase family may be responsible for the hybridisation to chromosome 17.     

A genetically controlled pairing anomaly between HLA-DQ alpha and HLA-DQ beta chains

The HLA-DQ region contains highly polymorphic alpha and beta loci, so that a diverse set of cis- and trans-associated class II alpha/beta dimers are potentially generated in heterozygous individuals. To evaluate the extent of this predicted diversity, DQ2 beta or DQ3.2 beta cDNA were introduced into a panel of homozygous B cell lines that expressed different DQ alpha alleles. Restricted patterns of alpha/beta pairing were observed in which DQ2 beta and DQ3 beta molecules were unable to pair efficiently with DQ1 alpha chains. This pairing anomaly may contribute to altered class II phenotypes in heterozygous individuals, and is reflected in the absence of either DQ1 alpha, DQ2 beta or DQ1 alpha, DQ3 beta haplotypes in the known human gene pool.     

Chromosomal localization of GABAA receptor subunit genes: relationship to human genetic disease

Hybridization of GABAA receptor probes to human chromosomes in situ and to DNA from sorted human chromosomes has localized the genes encoding a beta subunit and three isoforms of the alpha subunit. The alpha 2 and beta genes are both located on chromosome 4 in bands p12-p13 and may be adjacent. The alpha 1 gene is on chromosome 5 (bands q34-q35) and the alpha 3 gene is on the X chromosome. The alpha 3 locus was mapped also on the mouse X chromosome using genetic break-point analysis in an interspecies pedigree. The combined results locate the human alpha 3 gene within band Xq28, in a location that makes it a candidate gene for the X-linked form of manic depression.     

Assignment of first random restriction fragment length polymorphism (RFLP) locus ((D14S1) to a region of human chromosome 14.

A locus responsible for a restriction fragment length polymorphism (RFLP) has been identified by hybridization of Eco RI fragments to the random human DNA sequence in recombinant plasmid pAW101. We have examined DNA extracted from 20 human X Chinese hamster somatic cell hybrids for the presence of sequences homologous to the human insert in pAW101. The hybrids were derived from six different human donors, five of whom were heterozygous, producing two bands on Southern transfers. The presence of homologous sequences in the hybrids correlated exclusively with the presence of human chromosome 14. Three hybrids contained chromosome 14 in a frequency of greater than one per cell and were positive for two alleles. Two hybrids contained only the distal half of the long arm of 14 as part of a translocation and were still positive. These results assign the first highly polymorphic random RFPL locus (D14S1) to region q21 leads to qter of chromosome 14.     

Linkage of bovine erythrocyte antigen loci B, C, L, S, Z, R' and T' and the serum protein loci post-transferrin 2 (PTF 2), vitamin D binding protein (GC) and albumin (ALB) to DNA microsatellite markers

Seven bovine erythrocyte antigen loci and three serum protein loci were tentatively assigned to chromosomes or synteny groups by linkage analysis to previously assigned microsatellite DNA markers. The erythrocyte antigen locus EAB was mapped to synteny group U27; EAC to chromosome 18, synteny group U9; EAL to chromosome 3, synteny group U6; EAS to chromosome 21, synteny group U4; EAZ to chromosome 10, synteny group U5; EAR' to chromosome 16, synteny group U1; and EAT' to chromosome 19, synteny group U21. The vitamin D binding protein (GC) and albumin (ALB) loci were assigned to chromosome 6, synteny group U15 and post-transferrin 2 (PTF 2) to chromosome 19, synteny group U21.     

Regional assignment of two genes of the human branched-chain alpha-keto acid dehydrogenase complex: the E1 beta gene (BCKDHB) to chromosome 6p21-22 and the E2 gene (DBT) to chromosome 1p31

Maple syrup urine disease (MSUD) is caused by the deficiency of the mitochondrial branched-chain alpha-keto acid dehydrogenase complex. The multienzyme complex is a macromolecule (Mr 4 X 10(6] consisting of at least six distinct subunits. In this study, the human E1 beta gene (BCKDHB) has been localized to human chromosome 6 by hybrid somatic cell analysis, and regionally assigned to chromosome bands 6p21-22 by in situ hybridization. The E2 gene (DBT), which was previously localized to chromosome 1, is regionally assigned to the chromosome band 1p31 also by in situ hybridization. Localization of the E1 beta gene to chromosome 6p21-22 assigns another major human disease locus to a region that contains several important genes, including the major histocompatability complex, tumor necrosis factor, and heat-shock protein HSP70. Mapping of the E1 beta and the E2 genes may provide information for the linkage analysis of MSUD families with mutations in these two loci.     

DLX2 (TES1), a homeobox gene of the Distal-less family, assigned to conserved regions on human and mouse chromosomes 2.

Dlx-2 (also called Tes-1), a mammalian member of the Distal-less family of homeobox genes, is expressed during murine fetal development in spatially restricted domains of the forebrain. Searching for a candidate neurological mutation that might involve this gene, we have assigned the human and mouse loci to regions of conserved synteny on human chromosome 2, region cen--q33, and mouse chromosome 2 by Southern analysis of somatic cell hybrid lines. An EcoRI dimorphism, discovered in common inbred laboratory strains, was used for recombinant inbred strain mapping. The results place Dlx-2/Tes-1 near the Hox-4 cluster on mouse chromosome 2.     

The Genetics of a Small Autosomal Region of DROSOPHILA MELANOGASTER Containing the Structural Gene for Alcohol Dehydrogenase. I. Characterization of Deficiencies and Mapping of ADH and Visible Mutations

The position of the structural gene coding for alcohol dehydrogenase (ADH) in Drosophila melanogaster has been shown to be within polytene chromosome bands 35B1 and 35B3, most probably within 35B2. The genetic and cytological properties of twelve deficiencies in polytene chromosome region 34--35 have been characterized, eleven of which include Adh. Also mapped cytogenetically are seven other recessive visible mutant loci. Flies heterozygous for overlapping deficiencies that include both the Adh locus and that for the outspread mutant (osp: a recessive wing phenotype) are homozygous viable and show a complete ADH negative phenotype and strong osp phenotype. These deficiencies probably include two polytene chromosome bands, 35B2 and 35B3.     

Syntenic conservation between humans and cattle. I. Human chromosome 9

Bovine X hamster hybrid somatic cells have been used to investigate the syntenic relationship of nine loci in the bovine that have homologous loci on human chromosome 9. Six loci, ALDH1, ALDOB, C5, GGTB2, GSN, and ITIL, were assigned to the previously identified bovine syntenic group U18 represented by ACO1, whereas the other three loci, ABL, ASS, and GRP78, mapped to a new, previously unidentified autosomal syntenic group. Additionally, a secondary locus, ABLL, which cross-hybridized with the ABL probe, was mapped to bovine syntenic group U1 with the HSA 1 loci PGD and ENO1. The results predict that ACO1 will map proximal to ALDH1; GRP78 distal to ITIL and C5; GSN proximal to AK1, ABL, and ASS on HSA 9; GRP78 to MMU 2; and ITIL and GSN to MMU 4.     

Chromosomal localization of human genes required for G1 progression in mammalian cells

Specific probes derived from the human genes that complement the mutations of two independent temperature-sensitive (ts) mutants of the BHK-21 hamster cell line were used to determine the chromosomal locations of the loci in the human genome. The ts11 gene, which complements a mutation that blocks progression through the G1 phase of the cell cycle and which has now been identified as the structural gene for asparagine synthetase, is a member of a small gene/pseudogene family with four members. In a rodent-human somatic cell hybrid panel, the ts11 genomic locus from which the genomic probe derives segregates with human chromosome region 7cen----7q35, proximal to the TCR beta locus. In situ hybridization maps this locus more precisely to the q21-31 region of chromosome 7. Two other members of the gene family detected by the ts11 probe segregate concordantly with chromosome region 8pter----8q24 and chromosome region 21pter----21q22. Similar experiments using the same rodent-human hybrid panel conducted with a probe identifying the tsBN51 gene, which also encodes a function necessary for G1 progression, mapped this locus to human chromosome 8, proximal to the large amplification unit encompassing the c-myc gene of Colo320 cells. Chromosomal in situ hybridization of the tsBN51 probe confirmed the localization of this gene to chromosome 8, with the most likely location of the gene being 8q21.     

Assignment of the human gene for muscle-type phosphofructokinase (PFKM) to chromosome 1 (region cen leads to q32) using somatic cell hybrids and monoclonal anti-M antibody

Human phosphofructokinase (PFK; EC 2.7.1.11) is under the control of three structural loci which encode muscle-type (M), live-type (L), and platelet-type (P) subunits; human diploid fibroblasts and leukocytes express all three loci. In order to assign human PFKM locus to a specific chromosome we have analyzed human x Chinese hamster somatic cell hybrids for the expression of human M subunits, using an anti-human M subunit-specific mouse monoclonal antibody. In 18 of 19 hybrids studied, the expression of the PFKM locus segregated concordantly with the presence of chromosome 1 (discordance rate 0.05) as indicated by chromosome and isozyme marker analysis. The discordance rates for all the other chromosomes were 0.32 or greater, indicating that the PFKM locus is on chromosome 1. For the regional mapping of PFKM, eight hybrids were studied that contained one of five distinct regions of chromosome 1. These results further localize the human PFKM locus to region cen leads to q32 chromosome 1.     

Assignment of the alpha 1-antitrypsin gene and a sequence-related gene to human chromosome 14 by molecular hybridization

alpha 1-Antitrypsin is a major plasma protease inhibitor synthesized in the liver. Genetic deficiency of this protein predisposes the affected individuals to development of infantile liver cirrhosis or chronic obstructive pulmonary emphysema. The human chromosomal alpha 1-antitrypsin gene has been cloned and shown to contain three introns in the peptide-coding region. When the cloned alpha 1-antitrypsin gene was used as a hybridization probe to analyze Eco RI-digested genomic DNA from different individuals, two distinct bands of 9.6 kilobases (kb) and 8.5 kb in length were observed in every case. Further analysis using only labeled intronic DNA as the hybridization probe has indicated that the authentic alpha 1-antitrypsin gene resides within the 9.6-kb fragment. Thus the 8.5-kb fragment must contain another gene that is closely related in sequence to the alpha 1-antitrypsin gene. Using a series of human-Chinese hamster somatic cell hybrids containing unique combinations of human chromosomes, the alpha 1-antitrypsin gene as well as the sequence-related gene have been assigned to human chromosome 14 by Southern hybridization and synteny analysis.     

Mapping of Col3a1 and Col6a3 to proximal murine chromosome 1 identifies conserved linkage of structural protein genes between murine chromosome 1 and human chromosome 2q

We have investigated the degree of synteny between the long arm (q) of human chromosome 2 and the proximal portion of mouse chromosome 1. To define the limits of synteny, we have determined whether mouse homologs of seven human genes mapping to chromosome 2q cosegregated with anchor loci on mouse chromosome 1. The loci investigated were NEB/Neb, ELN/Eln, COL3A1/Col3a1, CRYG/Len-2, FN1/Fn-1, VIL/Vil, and COL6A3/Col6a3. Ren-1,2 and Acrg were included as two proximal mouse chromosome 1 anchor loci. The segregation of restriction fragment length polymorphisms at these loci was analyzed in the progeny of Mus spretus x C57BL/6J hybrids backcrossed to the C57BL/6J inbred strain. We found that five of the structural protein loci and the two anchor loci form a linkage group on proximal murine chromosome 1. The proposed gene order of this group of linked markers is centromere - Col3a1 - Len-2-Fn-1-Vil-Acrg-Col6a3-Ren1,2. Neb and Eln are linked neither to each other nor to any other marker on proximal mouse chromosome 1. Therefore, the mouse loci Col3a1 and Col6a3 are identified as flanking markers of the linkage group of structural protein loci. The estimated genetic map distances are Col3a1-13.3 cM-Len-2-3.4 cM-Fn-1-3.8 cM-Vil-9.6 cM-Acrg-2.1 cM-Col6a3-18.3 cM-Ren1,2. The available map information for human chromosome 2q markers and mouse chromosome 1 markers presented here tentatively identifies Col3a1 and Col6a3 as the border markers that define the limits of the syntenic chromosome segment. The order of mouse genes on chromosome 1 and their human homologs on chromosome 2q also appears to be conserved, suggesting that mapping of murine genes on the conserved segment may be useful to predict gene order in man.     

Assignment of human genes for phosphorylase kinase subunits alpha (PHKA) to Xq12-q13 and beta (PHKB) to 16q12-q13.

Phosphorylase kinase (PHK), the enzyme that activates glycogen phosphorylases in muscle, liver, and other tissues, is composed of four different subunits. Recently isolated rabbit muscle cDNAs for the larger two subunits, alpha and beta, have been used to map the location of their cognate sequences on human chromosomes. Southern blot analysis of rodent x human somatic cell hybrid panels, as well as in situ chromosomal hybridization, have provided evidence of single sites for both genes. The alpha subunit gene (PHKA) is located on the proximal long arm of the X chromosome in region Xq12-q13 near the locus for phosphoglycerate kinase (PGK1). X-linked mutations leading to PHK deficiency, known to exist in humans and mice, are likely to involve this locus. This hypothesis is consistent with the proximity of the Phk and Pgk-1 loci on the mouse X chromosome. In contrast, the beta subunit gene (PHKB) was found to be autosomal and was mapped to chromosome 16, region q12-q13 on the proximal long arm. Several different autosomally inherited forms of PHK deficiency for which the PHKB could be a candidate gene have been described in humans and rats.     

Localization on pig chromosome 6 of markers GPI, APOE, and ENO1, carried by human chromosomes 1 and 19, using in situ hybridization

In the pig, the linkage group around the halothane gene (HAL), composed of S-GPI-HAL-H-A1BG-PGD, has been assigned to bands p1.2----q2.2 of chromosome 6. In man, ENO1-PGD and APOE-GPI constitute two syntenic groups situated on different chromosomes (1 and 19, respectively). Since GPI and PGD are linked in the pig, we have hybridized the human cDNA probes for ENO1 and APOE to pig chromosomes. These markers were assigned to pig chromosome 6, in the q2.2----q2.4 and cen----q2.1 regions, respectively, using in situ hybridization. Since GPI and APOE are situated in the same region, we combined the use of high resolution chromosome analysis and in situ hybridization to give a more precise localization in the q1.2 and q1.2----q2.1.2 regions of chromosome 6. A possible linear order of these genes is proposed.     

Proteomic features of potential tumor suppressor NESG1 in nasopharyngeal carcinoma

We previously defined the recently revised NESG1 gene as a potential tumor suppressor in nasopharyngeal carcinoma (NPC). Here, we further used proteomics technology to globally examine NESG1‐controlled proteins in NPC cells. Twenty‐six proteins were found to be deregulated by NESG1 using proteomics analysis while enolase 1 (alpha) (ENO1), heat shock protein 90 kDa beta (Grp94), member 1 (HSP90B1), and cathepsin D (CTSD) proteins were differentially expressed by Western blot. Interestingly, a‐enolase (ENO1), an overexpressed gene in NPC, was confirmed as a NESG1‐regulated protein in NPC cells. Overexpressed ENO1 not only restored cell proliferation and cell‐cycle progression, but also antagonized the regulation of NESG1 to cell‐cycle regulators p21 and CCNA1 expression as well as induced the expression of C‐Myc, pRB, and E2F1 in NESG1‐ovexpressed NPC cells. Real‐time PCR and immunohistochemistry analysis showed that NESG1 expression is negatively correlated with ENO1 expression in NPC tissues. Our observations suggest that ENO1 downregulation plays an important role in NESG1‐induced growth inhibition of NPC cancer cells.     

Chromosomal assignment of genes encoding the alpha, beta, and gamma subunits of human complement protein C8: identification of a close physical linkage between the alpha and the beta loci

The eighth component of human complement (C8) is a serum protein containing three nonidentical subunits (alpha, beta, gamma) that are arranged as a disulfide-linked alpha-gamma dimer and a noncovalently associated beta chain. In earlier genetic studies, electrophoretic analysis of C8 protein polymorphisms revealed several allelic variants of alpha-gamma and beta. These were governed by separate loci designated C8A and C8B for alpha-gamma and beta, respectively. Genetic linkage analyses indicated that these loci were linked to each other and to chromosome 1 marker loci PGM1 and Rh, but it was unclear at the time if C8A was a single locus coding for a single-chain precursor form of alpha-gamma or if separate loci existed for alpha and gamma. Since evidence now indicates that alpha, beta, and gamma are encoded by separate genes, cDNA probes corresponding to each subunit were used to make direct assignments of the individual loci. Analysis of somatic cell hybrids revealed that only the alpha and beta loci are located on chromosome 1. Parallel analysis of genomic DNA digests using 5' and 3'-specific cDNA probes showed they are physically linked (less than 2.5 kb) and oriented 5' alpha-beta 3'. Further probing of the hybrid panel revealed that gamma is located on chromosome 9q. Thus, the observed genetic linkage of alpha-gamma to beta must be determined solely by alpha. In accordance with these findings, the C8 loci should now be designated C8A, C8B, and C8G for alpha, beta and gamma, respectively.