Regional chromosomal assignment of the human glucocorticoid receptor gene to 5q31

Summary The gene for the human glucocorticoid receptor, previously mapped to chromosome 5, has been further localised to 5q31 by in situ hybridisation using a biotinylated 4.3-kb cDNA probe.     

Regional chromosomal assignment of the human mineralocorticoid receptor gene to 4q31.1

Summary The gene for human mineralocorticoid receptor (hMR), previously mapped to chromosome 4, has been further localized to 4q31.1 by in situ hybridization using a biotinylated 3.75kb human cDNA clone encoding the primary amino acid sequence of hMR as a probe. Preliminary comparative mapping studies in orangutan (Pongo pygmaeus) suggest localization of the probe to the long arm of chromosome 3.     

Regional localization of the human transferrin receptor gene to 3q26.2----qter.

Transport of iron across the cell membrane is mediated by the iron-binding serum protein, transferrin, and its cell-surface receptor. Transferrin receptor is required for cell proliferation and may play a functional role in the pathogenesis of iron-storage disorders and some neoplasias. To better understand the possible involvement of transferrin receptor in such disorders, we have determined the chromosomal locus of the receptor gene by in situ hybridization. The human transferrin receptor gene was thus mapped to 3q26.2----qter, a region of chromosome 3 that appears to be involved in metal transport and that is subject to nonrandom structural rearrangements associated with neoplasia.     

Mapping of human hexokinase 1 gene to 10q11----qter.

Two partial-length cDNAs encoding the type 1 human hexokinase (ATP:D-hexose 6-phosphotransferase) were isolated from a placenta cDNA library using a 50-bp oligonucleotide synthesized according to the known sequence of human HK1. Using the larger (1.8 kb) cDNA insert as a probe and a panel of human-hamster somatic cell hybrids, we were able to assign the HK1 gene to the long arm of chromosome 10.     

Regional mapping of the human renin gene to 1q32 by in situ hybridization

Renin, related to other aspartyl proteases, plays an important role in the cascade which regulates blood pressure and salt metabolism. A human renin 1 100 bp long cDNA including most of the coding region and the 3' non coding region has been subcloned by Soubrier et al., 1983. A 1000 b RNA probe derived by subcloning into pSP64 vector was hybridized to EcoRI and HindIII digests of the DNA of a panel of 24 man-rodent somatic cell hybrids. With HindIII, four restriction fragments were observed, two of them revealing polymorphism (8.4 kb and 6.0 kb). Analysis of the distribution of the human signal among the hybrids confirms the localization of the renin gene (REN) to human chromosome 1. The whole plasmid including the 1 100 bp long insert was used for regional mapping by in situ hybridization; 45% of silver grains were found on chromosome 1, with a clear peak at band 1q32 (33% of silver grains on chromosome 1) and a smaller one at band 1q42 (17%). These data favour a regional localization of the renin gene to 1q32-1q42. Mac Gill et al. (1987) have localized the REN gene to 1q25-1q32 using in situ hybridization. Thus, 1q32 could be the most probable localization. No other peak could be observed. This is in agreement with results obtained with somatic cell hybrids.     

Regional chromosomal assignment of the human platelet phosphofructokinase gene to 10p15

Summary A cDNA for human platelet 6-phosphofructokinase (PFKP) has been isolated from a human Raji cell line cDNA library. Using this cDNA as a probe, the gene for human PFKP, previously mapped to chromosome 10pter-p11.1, has been further localized to 10p15 by non-isotopic in situ hybridization.     

Chromosomal mapping of human kininogen gene (KNG) to 3q26----qter.

The structural gene for human kininogen (KNG) was localized to chromosome 3q26----qter by in situ hybridization. The assignment substantiates the evolutionary relationship of kininogen to two other members of the cystatin superfamily, alpha-2-HS-glycoprotein and histidine-rich glycoprotein, which also map to chromosome 3.     

Close linkage of the Wilsons's disease locus to D13S12 in the chromosomal region 13q21 and not to ESD in 13q14

Summary Wilson's disease (WD) is an autosomal recessive disorder resulting in copper accumulation notably in liver and brain tissue. Linkage of the WD locus (WND) to ESD at 13q14 was first shown by studies in families of Middle Eastern origin using the isozymic polymorphism of esterase D. Using RFLPs detected by the ESD cDNA we could not confirm this reported close linkage in an analysis of 17 WD families of northwest European origin. A tight linkage was detected, however, to the marker D13S12, located more distally at 13q21. No obligate cross-overs were detected in 63 gametes informative for this marker. Our data confirm an assignment of WND to 13q14-21. Its localization, however, seems to be more distal to ESD than previously reported. Although genetic heterogeneity cannot be excluded, the observed differences between the two populations are probably due to random variation.     

Tentative assignment of piebald trait gene to chromosome band 4q12

Summary A case of de novo del(4)(q12q21.1) is presented. Three of four patients with comparable deletion show abnormal integumentary pigmentation, which is compatible with the known autosomal dominantly inherited piebald trait. Further analysis of breakpoints of five cases with proximal interstitial 4q deletion suggests the possible localization of the piebald trait gene within the band 4q12.Dedicated to Professor Dr. med. G. G. Wendt, a founding editor of the journal, on the occasion of his 65th birthday     

Localization of the acetylcholine receptor gamma subunit gene to human chromosome 2q32----qter

The nicotinic acetylcholine receptor of skeletal muscle (CHRN in man, Acr in mouse) is a transmembrane protein composed of four different subunits (alpha, beta, gamma, and delta) assembled into the pentamer alpha 2 beta gamma delta. These subunits are encoded by separate genes which derive from a common ancestral gene by duplication. We have used a murine full-length 1,900-bp-long cDNA encoding the gamma subunit subcloned into M 13 (clone gamma 18) to prepare single-stranded probes for hybridization to EcoRI-digested DNA from a panel of human x rodent somatic cell hybrids. Using conditions of low stringency to favor cross-species hybridization, and prehybridization with rodent DNA to prevent rodent background, we detected a single major human band of 30-40 kb. The pattern of segregation of this 30-40 kb band correlated with the segregation of human chromosome 2 within the panel and the presence of a chromosomal translocation in the distal part of the long arm of this t(X;2)(p22;q32.1) chromosome allowing the localization of the gamma subunit gene (CHRNG) to 2q32----qter. The human genes encoding the gamma and delta subunits have been shown to be contained in an EcoRI restriction fragment of approximately 20 kb (Shibahara et al., 1985). Consequently, this study also maps the delta subunit gene (CHRND) to human chromosome 2q32.1----qter. In the mouse, the Acrd and Acrg genes have been shown to be linked to Idh-1, Mylf (IDH1 and MYL1 in humans, respectively) and to the gene encoding villin on chromosome 1. Interestingly, we have recently localized the human MYL1 gene to the same chromosomal fragment of human chromosome 2. These results clearly demonstrate a region of chromosomal homoeology between mouse chromosome 1 and human chromosome 2.     

The rat renin gene: assignment to chromosome 13 and linkage to the regulation of blood pressure.

It has recently been suggested that in the rat, sequence variation in the renin gene or closely linked genes may have the capacity to affect blood pressure and contribute to the pathogenesis of hypertension. To map the chromosomal location of the rat renin gene and to investigate its relationship to the inheritance of increased blood pressure, we studied a panel of rat x mouse somatic cell hybrids and a large set of recombinant inbred (RI) strains derived from spontaneously hypertensive rats (SHR) and normotensive Brown-Norway (BN) rats. We have found that in the rat, the renin gene is located on chromosome 13 and that it belongs to a conserved synteny group located on chromosome 1 in man and mouse. We have also found the median blood pressure of the RI strains that inherited the renin allele of the SHR to be greater than that of the RI strains that inherited the renin allele of the normotensive BN rat. These findings, together with the results of previous studies, suggest that in the rat, sequence variation in the renin gene, or in genes linked to the renin locus on chromosome 13, may have the capacity to affect blood pressure.     

Association of a new chromosomal deletion [del(1)(q32q42)] with diaphragmatic hernia: assignment of a human ferritin gene

Summary A newborn male with a large diaphragmatic hernia presented in severe respiratory distress. Additional features included a paucity of subcutaneous tissue, mild facial dysmorphism, webbing of the neck, genital hypoplasia, and flexion contractures of the fingers. His karyotype showed a previously unreported de novo interstitial deletion of the long arm of chromosome 1[46,XY,de(1)(pterq32.3::q42.3qter)]. Regional mapping of five human genes that have been provisionally assigned to chromosome 1 was performed by restriction analysis of genomic DNA from this patient. Glucocerebrosidase, H4 histone, renin, and alpha-spectrin genes mapped outside the delected region, whereas an H subunit of the ferritin gene mapped to 1q32q42. These results indicate the utility of chromosomal deletions in gene mapping, and the importance of karyotype analysis in newborns with diaphragmatic hernias.     

Isolation, expression, and characterization of the human ZCRB1 gene mapped to 12q12

While isolating morphine-dependence-related genes with differential display, we cloned a novel human gene, zinc finger CCHC-type and RNA-binding motif 1 (ZCRB1, alias MADP-1) encoding a nuclear protein (217 residues). The ZCRB1 gene consists of eight exons and seven introns. It is mapped to 12q12, which is within a locus reported for Parkinson disease (M. Funayama et al., Ann. Neurol. 51 (2002) 296-301). The 5'-flanking region contains an enhancer core motif and binding sites for AP-1, AP-2, and LF-A1. ZCRB1 is characterized by an RNA-binding motif and a CCHC zinc finger motif. The latter overlaps the C..C...GH....C core nucleocapsid motif. ZCRB1 is conserved from zebrafish to human and shares homology with cold-inducible RNA-binding protein. Transfection assay showed that ZCRB1 is located in the nucleoplasm, but outside the nucleolus. ZCRB1 gene expression was stimulated by morphine, inhibited by 30-36 degrees C, and up-regulated by 39 degrees C incubation in SH-SY5Y neural cells. Zcrb1 gene expression is highest in the heart and testes, lower in the cerebellum, and lowest in the liver in mice. ZCRB1 mRNA expression is specifically elevated in hepatocarcinoma HepG2 cells. These data provide new clues for further understanding of morphine dependence, heat shock, and hepatocarcinoma.     

Regional assignment of the human cell cycle control gene CDC2 to chromosome 10q21 by in situ hybridization

Summary The human homologue of the fission yeast cell control gene CDC2 has been assigned to human chromosome 10 at band q21 by in situ hybridization.     

Localisation of the human ABO: Np-1: AK-1 linkage group by regional assignment of AK-1 to 9q34

Summary Quantitative red cell adenylate kinase (AK-1) assay has been used in 8 patients with partial duplication or deletion of chromosome 9 in an attempt to find the precise intrachromosomal location of the structural gene locus. All regions of chromosome 9 are represented in abnormal dosage in at least one patient. A 43% increase in AK-1 activity was found to be associated with duplication of the terminal band of the long arm of chromosome 9. Duplication of all other parts of chromosome 9 were associated with normal enzyme activity. These findings not only confirm the assignment of the AK-1 locus to chromosome 9 made previously in somatic cell hybrids, but suggest a more precise assignment to region 9q33qter. This places the ABO: Np-1: AK-1 linkage group at the distal end of the long arm of chromosome 9.     

Evidence in favor of linkage to human chromosomal regions 18q, 5q and 13q for bicuspid aortic valve and associated cardiovascular malformations

The aim of this study was to identify regions of the genome that harbor genes influencing inheritance of bicuspid aortic valve (BAV) and/or associated cardiovascular malformation (CVM). Aortic valve disease is an important clinical problem, which often results in valve replacement, the second most common cardiac surgery in the United States. In every age group, a majority of cases of valve disease involves a BAV. BAV is the most common CVM with a reported prevalence of 1–2%. Heritability studies indicate that BAV determination is almost entirely genetic. We used a family-based genome-wide linkage analysis with microsatellite markers. Parametric and nonparametric analyses were performed with the software GENEHUNTER and SOLAR (Sequential Oligogenic Linkage Analysis Routines). Thirty-eight families (353 subjects) with BAV and/or associated CVM were assessed. Each participant underwent a standardized echocardiographic examination. The highest LOD score, 3.8, occurred on chromosome 18q between markers D18S68 and D18S1161. Two other chromosomal regions, 5q15–21 (between D5S644 and D5S2027) and 13q33-qter (between D13S1265 and 13qter), exhibited suggestive evidence of linkage (LOD > 2.0). Further, two previously reported linkage peaks on 9q34 and 17q24 were replicated in family specific analyses. No significant X chromosome linkage peaks were identified. In this genome-wide scan we demonstrate for the first time, that BAV and/or associated CVM exhibit linkage to chromosomes 18q, 5q and 13q. These regions likely contain genes whose mutation results in BAV and/or associated CVM indicating their important role in valvulogenesis and cardiac development. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Lisa J. Martin and Vijaya Ramachandran have contributed equally to this work.     

Sib pair linkage analysis of renin gene haplotypes in human essential hypertension

Summary Although essential arterial hypertension is believed to have a strong genetic predisposition, the gene(s) responsible are unknown. The mechanisms underlying the regulation of blood pressure and experimental studies place the renin gene among the main candidate genes that need to be tested in humans. We tested the hypothesis of a linkage between the renin gene and essential hypertension using the affected sib pair method. Siblings (133 subjects, 52.1±10.9 years) from 57 families were selected for sustained hypertension (160.7 ± 22.9/99.5 ± 12.8 mmHg with 80% of patients under antihypertensive treatment), of early onset (40.7 ± 12.0 years), in the absence of obesity, diabetes mellitus, and secondary hypertension. Eight renin haplotypes were generated from three diallelic renin restriction fragment length polymorphisms (RFLPs) (TaqI, Hinfi, HindIII) located throughout the renin gene. The allelic concordance between the sib pairs was analyzed by identity by state relationships for 98 sib pairs (41 for 41 couples, 39 for 13 trios, 18 for 3 quartets). Allelic frequencies in the 57 hypertensive probands were similar to those observed among 102 hypertensive subjects studied previously. Six of eight possible haplotypes were observed, the informativity of the marker corresponded to 70% of heterozygosity. Allelic concordance for all sib pairs according to sibship size was not significantly different from that expected under the hypothesis of no linkage (t = 0.52, P = 0.15) reflecting only a small excess of renin alleles shared by the hypertensive sibs (1.44 ± 0.6 vs 1.36 ± 0.6). Likewise the linkage hypothesis was unsupported by weighted estimates to correct for possible bias due to large sibship size. Thus, the sib pair analysis suggests that the renin gene does not have a frequent role in the pathogenesis of essential hypertension; further more powerful linkage studies or other approaches will be needed to detect contributions at the renin locus to the heritability of essential hypertension.     

Regional chromosomal assignment of human 3-beta-hydroxy-5-ene steroid dehydrogenase to 1p13.1 by non-isotopic in situ hybridisation

Summary In situ hybridisation using a biotinylated 1.2-kb human cDNA clone for human 3-beta-hydroxy-5-ene steroid dehydrogenase (HSD) supports the provisional regional localisation of the HSD gene to chromosome 1p13 and refines this localisation to 1p13.1.     

Evidence for the assignment of GUK 1 gene locus to 1q32 leads to q43 segment from gene dosage effect

A male infant with dup (1) (q32 leads to q43) constitution is reported. He had mental and physical retardation and a constellation of dysmorphisms, which are considered characteristic of trisomics for the distal one-third of the long arm of chromosome 1. The assay for guanylate kinase 1 (GUK 1) activity showed a gene dosage effect and confirmed the regional assignment of this marker in the chromosomal region indicated by data derived from somatic hybrids.