The Human Intron-Containing Gene for Glycogenin Maps to Chromosome 3, Band q24

Glycogenin is the autocatalytic, self-glucosylating primer for glycogen synthesis, providing the anchor on which the macromolecule is constructed. We have sequenced the cDNA coding for human muscle glycogenin and have deduced the corresponding amino acid sequence. By means of the polymerase chain reaction and fluorescencein situhybridization, we have found the chromosomal location of the gene coding for glycogenin. This is localized to human chromosome 3, band q24.     

The Protein Tyrosine Phosphatase ? Gene Maps to Mouse Chromosome 7 and Human Chromosome 10q26

We have mapped the mouse protein tyrosine phosphatase ? (PTP?, gene symbolPtpre) gene to the distal region of chromosome 7 by linkage analysis using two sets of multilocus genetic crosses. The humanPTP? gene (gene symbolPTPRE) was mapped to chromosome 10q26 by fluorescencein situhybridization. We have previously documented the existence of two isoforms ofPTP?—a transmembranal, receptor-type isoform and a shorter, cytoplasmic one. Both isoforms have been suggested to arise from a single gene through the use of alternative promoters and 5′ exons. The identification of a singlePTP? locus in both organisms is consistent with this suggestion.     

Human Fas Associated Factor 1, hFAF1, Gene Maps to Chromosome Band 1p32

Human Fas associated factor 1 protein (hFAF1) is involved in the positive regulation of Fas signaling even though it can not initiate the signal for itself. By chromosomal assignment using somatic cell hybrids (CASH), the hFAF1 gene was located on human chromosome 1 between markers D1S443 and D1S197. The hFAF1 gene was mapped to human chromosome band 1p32 by FISH utilizing a genomic PAC clone containing the gene. In genomic Southern analysis using hFAF1 cDNA as a probe, several bands appeared in three different restriction enzyme digestions. The single band appearance in FISH analysis compared to several bands in Southern blots implies that the hFAF1 gene would be rather big or that an additional hFAF1 gene isotype(s) might be present in close vicinity.     

The Gene Encoding Protein Kinase SEK1 Maps to Mouse Chromosome 11 and Human Chromosome 17

We report the mapping of the human and mouse genes encoding SEK1 (SAPK/ERK kinase-1), a newly identified protein kinase that is a potent physiological activator of the stress-activated protein kinases. The human SERK1 gene was assigned to human chromosome 17 using genomic DNAs from human–rodent somatic cell hybrid lines. A specific human PCR product was observed solely in the somatic cell line containing human chromosome 17. The mouseSerk1gene was mapped to chromosome 11, closely linked toD11Mit4,using genomic DNAs from a (C57BL/6J ×Mus spretus)F₁×M. spretusbackcross.     

N-Cadherin Gene Maps to Human Chromosome 18 and Is Not Linked to the E-Cadherin Gene

cDNA clones encoding the human N-cadherin cell adhesion molecule have been isolated from an embryonic muscle library by screening with an oligonucleotide probe complementary to the chick brain sequence and chick brain cDNA probe lambda N2. Comparison of the predicted protein sequences revealed greater than 91% homology between chick brain, mouse brain, and human muscle N-cadherin cDNAs over the 748 amino acids of the mature, processed protein. A single polyadenylation site in the chick clone was also present and duplicated in the human muscle sequence. Immediately 3' of the recognition site in chick a poly(A) tail ensued; however, in human an additional 800 bp of 3' untranslated sequence followed. Northern analysis identified a number of major N-cadherin mRNAs. These were of 5.2, 4.3, and 4.0 kb in C6 glioma, 4.3 and 4.0 kb in human foetal muscle cultures, and 4.3 kb in human embryonic brain and mouse brain with minor bands of 5.2 kb in human muscle and embryonic brain. Southern analysis of a panel of somatic cell hybrids allowed the human N-cadherin gene to be mapped to chromosome 18. This is distinct from the E-cadherin locus on chromosome 16. Therefore, it is likely that the cadherins have evolved from a common precursor gene that has undergone duplication and migration to other chromosomal locations.     

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.     

The Human Erythroid-Specific Transcription Factor EKLF Localizes to Chromosome 19p13.12–p13.13

Erythroid Krüppel-like factor (EKLF) is atrans-acting factor that binds specifically to the β-globin promoter CACCC box. EKLF is essential for adult erythroid development in mice. We have cloned and sequenced a cDNA encoding the human homologue of this gene, which shares 69% identity with the mEKLF protein. The expression of hEKLF is restricted to fetal liver and adult bone marrow. The genomic locus of hEKLF was mapped to chromosomal band 19p13.12–p13.13, using fluorescencein situhybridization.     

Mapping of theARIXHomeodomain Gene to Mouse Chromosome 7 and Human Chromosome 11q13

The recently described homeodomain protein ARIX is expressed specifically in noradrenergic cell types of the sympathetic nervous system, brain, and adrenal medulla. ARIX interacts with regulatory elements of the genes encoding the noradrenergic biosynthetic enzymes tyrosine hydroxylase and dopamine β-hydroxylase, suggesting a role for ARIX in expression of the noradrenergic phenotype. In the study described here, the mouse and human ARIX genes are mapped. Using segregation analysis of two panels of mouse backcross DNA, mouseArixwas positioned approximately 50 cM distal to the centromere of chromosome 7, nearHbb.HumanARIXwas positioned through analysis of somatic cell hybrids and fluorescencein situhybridization of human metaphase chromosomes to chromosome 11q13.3–q13.4. These map locations extend and further define regions of conserved synteny between mouse and human genomes and identify a new candidate gene for inherited developmental disorders linked to human 11q13.     

The Gene for Death Agonist BID Maps to the Region of Human 22q11.2 Duplicated in Cat Eye Syndrome Chromosomes and to Mouse Chromosome 6

Cat eye syndrome (CES) is associated with a duplication of a segment of human chromosome 22q11.2. Only one gene,ATP6E, has been previously mapped to this duplicated region. We now report the mapping of the human homologue of the apoptotic agonistBidto human chromosome 22 near locus D22S57 in the CES region. Dosage analysis demonstrated thatBIDis located just distal to the CES region critical for the majority of malformations associated with the syndrome (CESCR), as previously defined by a single patient with an unusual supernumerary chromosome. However,BIDremains a good candidate for involvement in CES-related mental impairment, and its overexpression may subtly add to the phenotype of CES patients. Our mapping of murineBidconfirms that the synteny of the CESCR and the 22q11 deletion syndrome critical region immediately telomeric on human chromosome 22 is not conserved in mice.Bidand adjacent geneAtp6ewere found to map to mousechromosome 6, while the region homologous to the DGSCR is known to map to mouse chromosome 16.     

Localization of the -Glutamine Synthetase Gene to Chromosome 1q23

Glutamine synthetase (E.C. 6.3.1.2) is expressed throughout the body and plays an important role in controlling body pH and in removing ammonia from the circulation. The enzyme clears -glutamate, the major neurotransmitter in the central nervous system, from neuronal synapses. The enzyme is a very sensitive marker of many disease and aging processes, especially those involving reactive oxygen species. This report describes the localization of the enzyme to chromosome 1 by PCR analysis of a human/rodent somatic cell hybrid panel. We also describe the localization of a recently described pseudogene to chromosome 9. Further localization of the glutamine synthetase gene locus to 1q23 was accomplished by fluorescencein situhybridization. The glutamine synthetase gene was mapped to five CEPH megaYACs between the polymorphic PCR markers D1S117 and D1S466 by analysis of the Whitehead Institute's recently described chromosome 1 contig map.