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I Hansmann

Publications and source records attributed to I Hansmann.

At least 37 records · Page 2Linked to original sources
PubMed1994

Molecular structure and chromosomal mapping of the human homolog of the agouti gene.

The agouti (a) locus in mouse chromosome 2 normally regulates coat color pigmentation. The mouse agouti gene was recently cloned and shown to encode a distinctive 131-amino acid protein with a consensus signal peptide. Here we describe the cloning of the human homolog of the mouse agouti gene using an interspecies DNA-hybridization approach. Sequence analysis revealed that the coding region of the human agouti gene is 85% identical to the mouse gene and has the potential to encode a protein of 132 amino acids with a consensus signal peptide. Chromosomal assignment using somatic-cell-hybrid mapping panels and fluorescence in situ hybridization demonstrated that the human agouti gene maps to chromosome band 20q11.2. This result revealed that the human agouti gene is closely linked to several traits, including a locus called MODY (for maturity onset diabetes of the young) and another region that is associated with the development of myeloid leukemia. Initial expression studies with RNA from several adult human tissues showed that the human agouti gene is expressed in adipose tissue and testis.

Agouti Signaling Protein↗
PubMed1994

The gene for the amyloid precursor-like protein APLP2 is assigned to human chromosome 11q23-q25.

The human amyloid precursor-like protein APLP2 is a highly conserved homologue of a sequence-specific DNA-binding mouse protein with a predicted function in the cell cycle. Somatic cell hybrids segregating human chromosomes were used to assign the APLP2 gene to chromosome 11. Fluorescence in situ hybridization confirmed this assignment and further localized the gene to q23-q25.

Amyloid beta-Protein Precursor↗
PubMed1994

Interstitial deletion of 22q11 in DiGeorge syndrome detected by high resolution and molecular analysis.

Two patients with DiGeorge syndrome (DGS), one with and one without characteristic dysmorphic facial features, were studied by high resolution banding, fluorescence in situ hybridization (FISH) and quantitative Southern blotting. In both patients, even in the one with no typical facial stigmata, a microdeletion within 22q11.2 was detected. FISH analysis, in particular, is most useful in screening for 22q11.2 segmental monosomy in patients with DGS and DGS-related features.

Blotting, Southern↗
PubMed1994

A multilocus DNA fingerprint with built-in security devices.

An unusual case of paternity testing is reported in which determination of paternity was an essential part of a genetic diagnosis. A Y-chromosomal abnormality, observed in a 33-year-old male whose wife had experienced a series of spontaneous abortions, was not found in his alleged father. DNA fingerprinting with the oligonucleotide multilocus probe (CAC)5 yielded two aberrant bands for the proband, i.e. bands exhibited by neither parent. This finding resulted in a comparatively low paternity probability of 0.02934 which is suggestive of, but does not unequivocally prove, false paternity. Subsequent analysis with other multi- and single-locus systems, however, failed to confirm this preliminary result. The paternity probability computed on the basis of the single-locus systems was 0.99997, providing compelling evidence in favour of true paternity. The present case thus demonstrates that even when two mutations turn up in a DNA fingerprint, these may be readily recognized as such.

Abortion, Spontaneous↗
PubMed1993

Cystatin C (CST3), the candidate gene for hereditary cystatin C amyloid angiopathy (HCCAA), and other members of the cystatin gene family are clustered on chromosome 20p11.2.

The cystatin C gene (CST3) encodes a low-molecular-weight cysteine proteinase inhibitor belonging to family II of the cystatin superfamily and is mutated in cases of hereditary cystatin C amyloid angiopathy (HCCAA). CST3, which along with other family II cystatin genes is a member of the cystatin gene family, has been assigned to chromosome 20. To investigate the genomic organization on chromosome 20, the CST3 gene and related sequences were regionally mapped by fluorescence in situ hybridization (FISH), Southern blot, and pulsed-field gel electrophoresis (PFGE) analysis using the cDNA cystatin C probe C6a and three genomic probes, C3E1, C3E2, and C3E2-2. Probe C3E2-2, which like probe C3E2 is specific for CST3, hybridized to only one HindIII and one XbaI fragment on Southern blots and to a 300-kb BssHII PFGE fragment. FISH with probe C3E2 mapped this locus to chromosome 20p11.2, with an FL-pter value of 0.37 +/- 0.07 on the physical map. Probe C3E1 containing the most conserved cystatin gene exon (exon 1) and its flanking sequences hybridized with more fragments, e.g., to eight XbaI and nine HindIII fragments on conventional Southern blots and to eight SmaI, two BssHII (900 and 300 kb), and two NotI fragments after PFGE. FISH with C3E1 revealed only one single site at 20p11.2 with an FL-pter value of 0.37 +/- 0.04, identical to that obtained with C3E2.(ABSTRACT TRUNCATED AT 250 WORDS)

Blotting, Southern↗
PubMed1993

High resolution mapping of interstitial long arm deletions of chromosome 16: relationship to phenotype.

The breakpoints of seven interstitial deletions of the long arm of chromosome 16 and two ring chromosomes of this chromosome were mapped by in situ hybridisation or by analysis of mouse/human somatic cell hybrids containing the deleted chromosome 16. Use of a high resolution cytogenetic based physical map of chromosome 16 enabled breakpoints to be assigned to an average resolution of at least 1.6 Mb. In general, interstitial deletions involving q12 or q22.1 have broadly similar phenotypes though there are differences in specific abnormalities. Deletions involving regions more distal, from 16q22.1 to 16q24.1, were associated with relatively mild dysmorphism. One region of the long arm, q24.2 to q24.3, was not involved in any deletion, either in this study or in any previous report. Presumably, monosomy for this region is lethal. In contrast, patients with deletions of 16q21 have a normal phenotype. These results are consistent with the proposed distribution of genes, frequent in telomeric Giesma light band regions but infrequent in G positive bands.

Abnormalities, Multiple↗
PubMed1993

A genetic map of chromosome 20q12-q13.1: multiple highly polymorphic microsatellite and RFLP markers linked to the maturity-onset diabetes of the young (MODY) locus.

Multiple highly polymorphic markers have been used to construct a genetic map of the q12-q13.1 region of chromosome 20 and to map the location of the maturity-onset diabetes of the young (MODY) locus. The genetic map encompasses 23 cM and includes 11 loci with PIC values > .50, seven of which have PICs > .70. New dinucleotide repeat polymorphisms associated with the D20S17, PPGB, and ADA loci have been identified and mapped. The dinucleotide repeat polymorphisms have increased the PIC of the ADA locus to .89 and, with an additional RFLP at the D20S17 locus, the PIC of the D20S17 locus to .88. The order of the D20S17 and ADA loci determined genetically (cen-ADA-D20S17-qter) was confirmed by multicolor fluorescence in situ hybridization. The previously unmapped PPGB marker is closely linked to D20S17, with a two-point lod score of 50.53 at theta = .005. These markers and dinucleotide repeat markers associated with the D20S43, D20S46, D20S55, D20S75, and PLC1 loci and RFLPs at the D20S16, D20S17, D20S22, and D20S33 have been used to map the MODY locus on chromosome 20 to a 13-cM (sex averaged) interval encompassing ADA, D20S17, PPGB, D20S16, and D20S75 on the long arm of chromosome 20 and to create a genetic framework for additional genetic and physical mapping studies of the region. With these multiple highly polymorphic loci, any MODY family of appropriate size can be tested for the chromosome 20 linkage.

Base Sequence↗
PubMed1992

Gene structure of semenogelin I and II. The predominant proteins in human semen are encoded by two homologous genes on chromosome 20.

The genes for semenogelin I and II, the major protein constituents of the human seminal fluid, have been characterized by three overlapping clones in bacteriophage lambda, encompassing 31.5 kilobases (kb) of genomic DNA. The two genes are located 11.5 kb apart in the region q12-q13.1 on chromosome 20. Both genes are relatively compact, spanning only 2.7 and 3.1 kb, respectively. The transcription units are composed of three exons, of which the first encodes the signal peptide, the second encodes the secreted protein, while the third solely contains 3'-noncoding nucleotides. The nucleotide sequences exhibit a similarity of close to 90% in the exons and exceeding 80% in the introns and flanking nucleotides.

Amino Acid Sequence↗
PubMed1992

Prenatal diagnosis of the Pallister-Killian mosaic aneuploidy syndrome by CVS.

Prenatal cytogenetic analysis at 11 weeks of gestation revealed an abnormal karyotype 47,XX,+mar in all metaphases obtained from a chorionic villi sample after 24 h culture. Karyotyping of amniotic fluid cells in the second trimester showed mosaicism 47,XX,+i(12p)/46,XX with 10% aneuploid cells. The pregnancy was terminated at 20 weeks of gestation on the patient's request. The aborted fetus showed typical manifestations of the Pallister-Killian mosaic aneuploidy syndrome. The identity of the supernumerary isochromosome 12p was proven by LDH isozyme electrophoresis using cultured fibroblasts and by nonradioactive in situ hybridization using a biotinylated set of chromosome 12-specific DNA probes.

Abnormalities, Multiple↗
PubMed1992

The gene for bone morphogenetic protein 2A (BMP2A) is localized to human chromosome 20p12 by radioactive and nonradioactive in situ hybridization.

Bone morphogenetic protein 2A (BMP2A), a member of the decapentaplegic-Vg-related family, belongs to the transforming growth factor beta superfamily and has a striking sequence similarity to the decapentaplegic locus in Drosophila melanogaster, a major determinant of pattern specification during embryogenesis. BMP2A is thought to be involved in cartilage and bone formation during embryogenesis, but may have additional functions in morphogenesis as implied by its expression in various organs and embryonic tissues of mice. Human BMP2A, assigned to chromosome 20 by the use of human-Chinese hamster ovary cell hybrids, is considered to be a reasonable candidate gene for the autosomal dominant disease of fibrodysplasia (myositis) ossificans progressiva. We have confirmed the localization of BMP2A to chromosome 20 and regionally assigned the locus to 20p12 by radioactive and nonradioactive in situ hybridization.

Bone Morphogenetic Proteins↗
PubMed1992

Pax1, a member of the paired box-containing class of developmental control genes, is mapped to human chromosome 20p11.2 by in situ hybridization (ISH and FISH).

Pax-1, a member of a murine multigene family, belongs to the paired box-containing class of developmental control genes first identified in Drosophila. The Pax-1 gene encodes a sequence-specific DNA-binding protein with transcriptional activating properties and has been found to be mutated in the autosomal recessive mutation undulated (un) on mouse chromosome 2 with vertebral anomalies along the entire rostrocaudal axis. By radioactive in situ hybridization (ISH) using a fragment from the murine Pax-1 paired box that is almost identical to the respective sequences from the cognate human gene HuP48 and fluorescence in situ hybridization (FISH) using a complete mouse Pax-1 cDNA, we have assigned the human homologue of murine Pax-1, the PAX1 locus, to chromosome 20p. The map position of PAX1 after FISH (FL-pter value of 0.34 +/- 0.04) corresponds to band p11.2. These results confirm the exceptional homology between human chromosome 20 and the distal segment of mouse chromosome 2, extending from bands F to G, and add PAX1 to the group of genes on 20p like PTPA, PRNP, SCG1, BMP2A, which are located in proximity on both chromosomes.

Animals↗
PubMed1992

The human gene for oxytocin-neurophysin I (OXT) is physically mapped to chromosome 20p13 by in situ hybridization.

Two posterior pituitary hormones oxytocin and arginine-vasopressin control the important activities of water excretion, parturition and lactation. Both these hormones are synthesized as inactive precursors in the hypothalamus along with their carrier proteins neurophysin I and neurophysin II respectively and are activated upon transport to posterior pituitary. Human genes for both oxytocin-neurophysin I (OXT) and arginine-vasopressin-neurophysin II (ARVP) are cloned and found to be linked on chromosome 20 separated by approximately 12 kb of intergenic sequences. Though OXT is not yet associated with any disease, ARVP is linked to the autosomal dominant disease neurohypophyseal diabetes insipidus (AD-NDI). We have mapped regionally the OXT locus to chromosome 20p13 by both radioactive (ISH) and fluorescence in situ hybridization (FISH).

Arginine Vasopressin↗
PubMed1991

A sterile male with 45,X0 and a Y;22 translocation.

Cytogenetic analysis of a 20-year-old sterile male revealed a 45,X0 karyotype with no evidence for Y-chromosomal material on any of the chromosomes analysed by Q-, G- and C-banding. DNA analysis with 17 different Y chromosome-derived probes revealed the presence of Yp DNA sequences in the patient's genome. In situ hybridization with the Yp-derived probe pJA36B disclosed a translocation of Y-chromosomal material onto the short arm of a chromosome 22.

Adult↗