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B Zoll

Publications and source records attributed to B Zoll.

At least 55 records · Page 3Linked to original sources
PubMed1991

Linkage data suggesting allelic heterogeneity for paramyotonia congenita and hyperkalemic periodic paralysis on chromosome 17.

Paramyotonia congenita (PC), an autosomal dominant non-progressive muscle disorder, is characterised by cold-induced stiffness followed by muscle weakness. The weakness is caused by a dysfunction of the sodium channel in muscle fibre. Parts of the gene coding for the alpha-subunit of the sodium channel of the adult human skeletal muscle (SCN4A) have been localised on chromosome 17. To investigate the role of this gene in the etiology of PC, a linkage analysis in 17 well-defined families was carried out. The results (zeta = 20.61, theta = 0.001) show that the mutant gene responsible for the disorder is indeed tightly linked to the SCN4A gene. The mutation causing hyperkalemic periodic paralysis (HyperPP) with myotonia has previously been mapped to this gene locus by the same candidate gene approach. Thus, our data suggest that PC and HyperPP are caused by allelic mutations at a single locus on chromosome 17.

Alleles↗
PubMed1991

The molecular genetics of haemophilia A: screening for point mutations in the factor VIII gene using the restriction enzyme TaqI.

A combination of Southern blotting and the analysis of polymerase chain reaction (PCR) amplified DNA fragments was used to screen the factor VIII genes of 527 haemophilia A patients for point mutations within TaqI restriction sites. Since this "directed search" strategy yielded only four gene lesions, it was concluded that its efficacy is less than that originally predicted. One novel point mutation was however found in a moderately severe haemophiliac; a CGA (Arg) to CTA (Leu) transversion at codon 2209, an evolutionarily conserved residue in the C2 domain of the factor VIII protein. The remaining three detected lesions, CGA (Arg)----TGA (Term) transitions at codons 2116, 2147 and 2307, respectively, have been reported before and are consistent with recurrent mutation at these hypermutable sites. A number of TaqI restriction site polymorphisms/rare variants were also noted. These variants appear to be population-specific but are nevertheless potentially useful in individual cases as intragenic markers for carrier detection and antenatal diagnosis.

Base Sequence↗
PubMed1991

Amplification of the c-erbB oncogene is associated with malignancy in primary tumours of neuroepithelial tissue.

In various primary brain tumours of neuroepithelial tissue recombinant DNA techniques were used to demonstrate changes of the epidermal growth factor receptor gene, which is homologous to the c-erbB oncogene. Twenty-one of 40 grade III/IV tumours, but only 1 of 16 grade I/II tumours were found to contain amplified and/or rearranged c-erbB sequences. This highly significant difference suggest that c-erbB amplification, rearrangement, or both, are important steps in malignant transformation in a subset of patients with neuroepithelial tumours.

Brain Neoplasms↗
PubMed1991

Carrier detection in haemophilia A by direct analysis of factor VIII gene lesions.

CGA----TGA (Arg----Term) transitions in the factor VIII gene causing severe haemophilia A were detected in two patients at codons 336 and 427 using a combination of oligonucleotide discrimination hybridization and DNA sequencing. Carrier detection analysis was then performed by polymerase chain reaction/direct sequencing of the appropriate region of the gene in female relatives of the probands.

Base Sequence↗
PubMed1991

Holt-Oram syndrome in four half-siblings with unaffected parents: brief clinical report.

The Holt-Oram syndrome was diagnosed in four offspring of three mothers and the same unaffected father. One additional child lacked the characteristic clinical features of the Holt-Oram syndrome. In contrast to the general autosomal dominant inheritance with complete penetrance, our observation suggests a paternal mutation, resulting in mosaicism, probably restricted to the germline.

Abnormalities, Multiple↗
PubMed1991

Saethre-Chotzen syndrome (ACS III) in four generations.

The acrocephalosyndactylies (ACS) are a group of inherited disorders characterized by premature fusion of cranial sutures in association with abnormalities of the hands and feet. Based on their clinical features, different types of ACS have been described. We here report on a family with 9 individuals affected with ACS III (Saethre-Chotzen syndrome), 5 of them severely. Clinical features of the patients are presented with regard to differential diagnostic delineations.

Acrocephalosyndactylia↗
PubMed1991

Confirmation of linkage of hyperkalaemic periodic paralysis to chromosome 17.

Linkage studies were performed in six European families with hyperkalaemic periodic paralysis (PPII) with myotonia, an autosomal dominantly inherited disorder characterised by episodic weakness. The weakness is caused by non-inactivating sodium channels of reduced single channel conductance of the muscle fibre membrane. Recently, portions of the gene coding for the alpha subunit of the sodium channel of the adult human skeletal muscle (h-Na2) have been cloned and localised on chromosome 17q with no recombinants to the human growth hormone locus (GH1). Linkage between these two chromosome 17 markers and the disease was shown in our families (Z = 7.14, 0 = 0.00). These results, combined with the linkage data of a single large American family, suggest that the disease is caused by dominant mutations of the adult sodium channel, and that it is probably a genetically homogeneous disorder. Hyperkalaemic periodic paralysis is the first non-progressive myotonic disorder to be localised on the human genome.

Chromosomes, Human, Pair 17↗
PubMed1990

Prenatal diagnosis and postnatal follow-up of a child with two de novo unrelated balanced reciprocal translocations.

Two unrelated, apparently balanced, reciprocal translocations involving chromosomes 3 and 17, and 10 and 15 were found in cultured amniotic fluid cells from a 41-year-old 10-gravida. Chromosome analysis of peripheral blood lymphocytes of both parents revealed normal karyotypes. Post-partum examination of lymphocyte cultures from the proband confirmed the chromosome rearrangements. The child showed normal development during follow-up examinations up to the age of 4 years.

Adult↗
PubMed1990

The molecular genetic analysis of haemophilia A; characterization of six partial deletions in the factor VIII gene.

In a survey of 528 unrelated haemophilia A patients, six partial deletions of the factor VIII (FVIII) gene were detected by Southern blotting. These deletions were further mapped by a combination of Southern blotting and polymerase chain reaction amplification and found to vary in length between 4.7 kb and 57 kb. The frequency of detectable FVIII gene deletions (about 1%) frequency of detectable FVIII gene deletions (about 1%) is thus considerably lower than previously reported. Statistical analysis of currently available data did not provide any evidence for a deletion "'hotspot". Four of the six deletion patients reported here possessed inhibitors. Taken together with previous data, deletion of the FVIII gene was found to be associated with an approximately five-fold higher risk of developing inhibitors compared with other severe haemophiliacs without gene deletions.

Blotting, Southern↗
PubMed1990

Diagnosis of haemophilia B using the polymerase chain reaction.

The polymerase chain reaction (PCR) was used to amplify specific DNA sequences within the factor IX gene of haemophilia B patients and their relatives. Three of the amplified fragments contain polymorphic sites, which can be used as markers in segregation analyses. These restriction fragment length polymorphisms (RFLPs) were until recently detected by Southern blotting after digestion with the restriction enzymes Taq I, Dde I and Xmn I. All three RFLP's are located in introns of the factor IX gene and together are informative in approximately 70% of all cases. Each of the polymorphisms was successfully used in carrier detection studies after amplification of the relevant fragments. This method is also suitable for rapid antenatal diagnosis. Additionally we were able to amplify all eight exons of the factor IX gene including the splice junctions and a part of the 5'-region. Large deletions or insertions can be detected without further analysis. Several possibilities for the rapid detection of point mutations after DNA amplification have been described recently. The complete amplification of all functional parts of the Factor IX gene in combination with these new techniques should enable us to detect the majority of mutations leading to haemophilia B.

Base Sequence↗
PubMed1989

Down syndrome at birth not detected by first-trimester chorionic villus sampling.

A case of a false-negative first-trimester diagnosis following chorionic villus sampling is reported that ended with the birth of a child with Down syndrome. Chromosome analysis of 30 metaphases from 24 h-cultured chorionic villi obtained in week 12 of gestation showed a normal chromosome constitution. However, the newborn showed manifestations of Down syndrome, and 99 of 100 metaphases analysed from cultured lymphocytes showed 47, XY, + 21. The remaining metaphase was normal (46, XY).

Chorionic Villi Sampling↗
PubMed1989

Myotonia congenita (Thomsen's disease) excluded from the region of the myotonic dystrophy locus on chromosome 19.

Linkage analysis has been carried out in six German families with autosomal dominantly inherited myotonia congenita (Thomsen's disease) using five chromosome 19 markers known to be linked to the gene for myotonic dystrophy (DM). Two of the markers, APOC1 and APOC2, are tightly linked to DM. Close linkage between these markers and myotonia congenita (MC) has been excluded to a distance of 9 cM (z = -2.158). These data support the clinical suggestion that MC and DM are non-allelic disorders.

Chromosomes, Human, Pair 19↗
PubMed1988

Evidence against a tumour-specific EcoRI RFLP of the c-mos locus.

EcoRI restriction fragment length polymorphisms (RFLP) at the human c-mos locus were analysed in DNAs of normal individuals and tumour patients. Two alleles with fragment lengths of 2.6 kb (A1) and 5.6 kb (A2) respectively were detected. The allele distribution among the tumour group was similar to that of the control group. No difference was found between the allele frequencies in leucocytes and tumour tissue DNA of the same patients.

Alleles↗
PubMed1988

Linkage relationship between retinoschisis and four marker loci.

The linkage relationship between the locus for juvenile retinoschisis (RS) and four X-chromosomal marker loci DXS9 (RC8), DXS16 (XUT23), DXS41 (99-6), and DXS43 (D2) has been studied in six families showing a history of this disease. Recombination with RS was found for all marker loci except DXS9. The maximum lod score is zeta = 2.66 for RS vs. DXS9 at a recombination fraction of theta = 0.0. Multipoint linkage analysis was performed and the locus order best supported by our data is: RS - DXS9 - DXS43 - DXS16 - DXS41.

Genetic Linkage↗
PubMed1988

Comparison between the allelic frequency distribution of the Ha-ras 1 locus in normal individuals and patients with lymphoma, breast, and ovarian cancer.

Analysis of 426 alleles of the human Ha-ras 1 locus in DNA samples of cancer patients and controls reveals no obvious association between specific restriction fragments and a genetic predisposition to malignancy. However, differences in the allele distribution in leukocyte and tumour DNAs of cancer patients may be related to an involvement of the Ha-ras 1 gene in tumorigenesis.

Alleles↗
PubMed1987

Segregation of all four major fibrillar collagen genes in the Marfan syndrome.

Linkage markers at or close to the genes encoding the three major fibrillar collagens were used to analyze the segregation of these loci in six pedigrees with dominantly inherited Marfan syndrome. Four pedigrees were discordant at one of the Type I collagen loci (COL1A2), and, of these, two were discordant at the other Type I locus (COL1A1). The Marfan syndrome also segregated independently of the structural loci for Type II and Type III collagen in these two families. This is evidence against the Marfan syndrome being, in general, due to mutations in the major fibrillar collagen genes.

Adolescent↗