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Biomedical subjects

M Burmeister

Publications and source records attributed to M Burmeister.

69 records · Page 4Linked to original sources
PubMed1992

Linkage studies in progressive myoclonus epilepsy: Unverricht-Lundborg and Lafora's diseases.

The progressive myoclonus epilepsies (PME) are a heterogeneous group of rare genetic disorders. Unverricht-Lundborg disease and Lafora's disease are two major classic forms of PME. We recently assigned the gene for Unverricht-Lundborg disease (EPM1) to human chromosome 21 band q22.3. We have now refined the localization of EPM1 by linkage analysis between the disease phenotype and nine DNA markers in 13 Finnish families. Loci MX1 and CD18 flank the EPM1 interval, which spans a distance of about 3.5 megabases. In this 20-centimorgan interval, no recombinations were detected between EPM1 and marker loci BCEI, D21S19, D21S42, D21S113, D21S154, and PFKL. Within this interval a maximum multipoint lod score of 11.04 was reached at loci D21S154-PFKL. In two Swedish families with Unverricht-Lundborg disease no recombinations were detected. In three Italian families with Lafora's disease the linkage results suggested that EPM1 is not the locus for Lafora's disease.

Chromosome Mapping↗
PubMed1991

TaqI RFLP at D21S137.

Explore the source record for details and available documents.

Chromosomes, Human, Pair 21↗
PubMed1991

Identification of polymorphisms by genomic denaturing gradient gel electrophoresis: application to the proximal region of human chromosome 21.

Genomic Denaturing Gradient Gel Electrophoresis (gDGGE) provides an alternative to the standard method of restriction fragment length polymorphism (RFLP) analysis for identifying polymorphic sequence variation in genomic DNA. For gDGGE, genomic DNA is cleaved by restriction enzymes, separated in a polyacrylamide gel containing a gradient of DNA denaturants, and then transferred by electroblotting to nylon membranes. Unlike other applications of DGGE, gDGGE is not limited by the size of the probe and does not require probe sequence information. gDGGE can be used in conjunction with any unique DNA probe. Here we use gDGGE with probes from the proximal region of the long arm of human chromosome 21 to identify polymorphic DNA sequence variation in this segment of the chromosome. Our screening panel consisted of DNA from nine individuals, which was cleaved with five restriction enzymes and submitted to electrophoresis in two denaturing gradient conditions. We detected at least one potential polymorphism for nine of eleven probes that were tested. Two polymorphisms, one at D21S4 and one at D21S90, were characterized in detail. Our study demonstrates that gDGGE is a fast and efficient method for identifying polymorphisms that are useful for genetic linkage analysis.

Chromosomes, Human, Pair 21↗
PubMed1991

Physical mapping of yeast artificial chromosomes containing sequences from the human beta-globin gene region.

The recently developed technique for cloning genomic DNA fragments of several hundred kilobases or more into yeast artificial chromosomes (YACs) makes it possible to isolate gene families while preserving their structural integrity. We have analyzed five independent yeast clones identified by PCR screening using oligonucleotides derived from the adult human beta-globin gene. Analysis of the five clones containing YACs by conventional and pulsed-field gel electrophoresis revealed that all of the clones include a YAC with sequences from the adult beta-globin gene as expected. One of the clones contains multiple, unstable YACs. Two other clones carry single YACs in which there are at least two unrelated human genomic inserts. The remaining two clones contain single YACs, 150 and 220 kb in size, that contain the entire beta-globin gene family and flanking regions in a single, structurally intact genomic fragment. These should prove useful in future studies of the regulation of expression of genes in the beta-globin gene cluster.

Cell Line↗
PubMed1991

A map of the distal region of the long arm of human chromosome 21 constructed by radiation hybrid mapping and pulsed-field gel electrophoresis.

We have used radiation hybrid (RH) mapping and pulsed-field gel electrophoresis (PFGE) to determine the order and positions of 28 DNA markers from the distal region of the long arm of human chromosome 21. The maps generated by these two methods are in good agreement. This study, combined with that of D. R. Cox et al. (1990, Science 250:245-250), results in an RH map that covers the long arm of chromosome 21 (21q). We have used a subtelomeric probe to show that our map includes the telomere and have identified single-copy genes and markers within 200 kbp of the telomere. Comparison of the physical and RH maps with genetic linkage maps shows "hot spots" of meiotic recombination in the distal region, one of which is close to the telomere, in agreement with previous cytogenetic observations of increased recombination frequency near telomeres.

Cell Line↗
PubMed1990

Radiation hybrid mapping: a somatic cell genetic method for constructing high-resolution maps of mammalian chromosomes.

Radiation hybrid (RH) mapping, a somatic cell genetic technique, was developed as a general approach for constructing long-range maps of mammalian chromosomes. This statistical method depends on x-ray breakage of chromosomes to determine the distances between DNA markers, as well as their order on the chromosome. In addition, the method allows the relative likelihoods of alternative marker orders to be determined. The RH procedure was used to map 14 DNA probes from a region of human chromosome 21 spanning 20 megabase pairs. The map was confirmed by pulsed-field gel electrophoretic analysis. The results demonstrate the effectiveness of RH mapping for constructing high-resolution, contiguous maps of mammalian chromosomes.

Animals↗
PubMed1988

Jekyll, a family of phage-plasmid shuttle vectors.

A series of shuttle vectors has been constructed, which consist of a plasmid carrying a polylinker sequence and an M13 origin integrated into a lambda vector. A short direct repeat flanking the plasmid allows plasmid excision by homologous recombination. Sequences are cloned into unique restriction sites within the plasmid, and can be recovered either in phage or plasmid form, or can be packaged further as single-stranded DNA phage. These vectors therefore combine the efficiency of phage lambda cloning and screening with the ease of handling or analysing plasmid or M13 clones.

Bacteriophage lambda↗
PubMed1988

A 10-megabase physical map of human Xp21, including the Duchenne muscular dystrophy gene.

Using pulsed-field gel electrophoresis and 12 Xp21-derived DNA probes, we have constructed a continuous restriction map spanning more than 4 million base pairs (4 Mbp), including the Duchenne muscular dystrophy gene of more than 2 Mbp. This detailed map is part of a less detailed map spanning 10 Mbp, also spanning the genes for glycerol kinase and congenital adrenal hypoplasia, constructed under electrophoresis conditions which separated DNA fragments in the range 200 to 4000 kbp. DNA from three different tissues was analyzed, and differential methylation was observed.

Chromosome Deletion↗
PubMed1987

Derivation of clones close to met by preparative field inversion gel electrophoresis.

The molecular analysis of genes identified by mutations is a major problem in mammalian genetics. As a step toward this goal, preparative field inversion gel electrophoresis (FIGE) was used to selectively isolate clones from the environment of genetically linked markers, and to select a subset of these clones containing sequences next to specific restriction sites rare in mammalian DNA. This approach has been used to generate a library highly enriched in sequences closely linked to the cystic fibrosis marker met. One clone derived from the end of a Not I restriction fragment containing the met sequence was analyzed in detail and localized within a long range map to a position 300 kilobase pairs 5' of the metD sequence.

Bacteriophage lambda↗
PubMed1987

Tyrosine aminotransferase and chymotrypsinogen B are linked to haptoglobin on human chromosome 16q: comparison of genetic and physical distances.

The loci for haptoglobin (HP) and tyrosine aminotransferase (TAT) are known to reside at 16q22. Chymotrypsinogen B (CTRB), which is syntenic with TAT and HP on mouse chromosome 8, has also been assigned to human chromosome 16 but has not been mapped regionally. A linkage analysis was carried out in 13 informative families using RFLPs for these three markers. For CTRB, two TaqI RFLPs with a polymorphism information content of 0.60 derived from haplotype frequencies are described. The most likely order of loci, deduced from triple informative crosses, and their map distances, obtained by pair-wise linkage analysis, are HP-7 cM-TAT-9 cM-CTRB. By pulsed-field gel electrophoresis, a physical map covering more than 2000 kb was constructed. A maximum physical distance of about 700 kb was obtained for HP and TAT, which contrasts with the genetic distance of 7 cM (approximate confidence limits 2-18 cM). CTRB is at least 800 kb away from these two markers.

Amino Acid Metabolism, Inborn Errors↗
PubMed1986

Development of additional RFLP probes near the locus for Duchenne muscular dystrophy by cosmid cloning of the DXS84 (754) locus.

We have isolated 70kb of sequences surrounding probe 754 (DXS84), linked with Duchenne muscular dystrophy. In addition to the original PstI RFLP detected by 754, BglII and EcoRI RFLPs were detected with the single copy subclone 754.11 and a HindIII RFLP with the subclone 754.6. The BglII and HindIII and HindIII RFLPs both have minor allele frequencies of 40%, as in PstI polymorphism. The EcoRI polymorphism has a minor allele frequency of 23%. Since a linkage disequilbrium is observed between these RFLPs (P less than 0.001), the BglII and the HindIII RFLPs do not contribute to the heterozygosity. However, the minor allele of the EcoRI RFLP segregates exclusively with the major haplotype of the PstI-BglII-HindIII complex, and consequently 47% of the homozygotes for the haplotype become heterozygous. As a result, the overall heterozygote frequency of the DXS84 locus increases from 50% to 65%.

Chromosome Mapping↗
PubMed1984

Production of EGF-containing polypeptides in Xenopus oocytes microinjected with submaxillary gland mRNA.

The biosynthesis of epidermal growth factor (EGF), a 6045 dalton mitogen produced in the mouse submaxillary gland under androgen regulation, was studied using Xenopus oocytes. Microinjection of total, unfractionated gland mRNA together with [35S]cysteine resulted in the production of a secretory polypeptide of approximately 9000 daltons, specifically immunoprecipitable with anti-EGF antibodies. A minor amount of a similarly immunoreactive 9000 dalton secretory polypeptide was produced from the sucrose gradient 9S fraction of gland mRNA. Other, more intensely labeled polypeptides, a cytoplasmic 125 000 dalton and a secretory 110 000 dalton protein were immunoprecipitated from oocytes injected with the greater than 25S mRNA fraction. The biosynthesis of both can hardly be detected in oocytes injected with unfractionated mRNA. All three polypeptides are produced under androgen regulation and share common immunoreactive properties. Northern blot analysis using a 76 nucleotide synthetic EGF cDNA probe revealed hybridization with a single 28S mRNA species. This, and the apparent interrelation between the three polypeptides, suggest that a gland-specific processing protein, encoded by a 9S mRNA, is required to produce the 9000 dalton pro-EGF from the nascent translation product of EGF mRNA.

Animals↗
PubMed1969

Chromosomal Location of a Gene Involved in Potassium Ion Uptake in Escherichia coli B.

A chromosomal lesion responsible for defective potassium ion uptake in Escherichia coli B has been mapped by use of standard interrupted-mating crosses. The mutation, kac-1, is in strain RD-2, which is deficient in K(+) intake, exchanges cell K(+) for extracellular isotope at a reduced rate, and has an abnormality of phosphorus metabolism associated with its potassium deficiency. This report places kac-1 at about 4 min clockwise from pro, close to gal. The locus of kac-1 is distinctly different from the potassium retention mutant in strain B-207, the only other potassium accumulation mutant mapped in E. coli so far. In this study, two other potassium accumulation mutations, kac-2 and kac-3, whose particular type of accumulation defects have not yet been determined, were mapped. These mutations are in the same region of the chromosome as kac-1.

Journal Article↗
PubMedDate not supplied

Long-range restriction map around the Duchenne muscular dystrophy gene.

Duchenne muscular dystrophy is an X-linked recessive disease affecting about 1 in 4,000 newborn boys. As in many other inherited diseases, the biochemical basis of the condition is unknown, and as yet there is no effective treatment. Translocations, deletions and other mutations leading to the DMD phenotype are distributed over a chromosomal area of large, but unknown size. Using pulsed-field gradient gel electrophoresis, we have now determined restriction maps of a major fraction of this area, covering two regions of three million basepairs in total, and used it to determine the position of several probes linked to DMD. The maps establish physical distances between structural changes associated with the DMD phenotype and provide evidence for a CpG-rich island proximal to the area containing translocations and deletions associated with the DMD phenotype.

Chromosome Deletion↗