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A Eigel

Publications and source records attributed to A Eigel.

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

Nonisotopic detection of mutations using a modified single-strand conformation polymorphism analysis.

This report describes a rapid convenient screening system with improved sensitivity to detect mutations in the cystic fibrosis transmembrane regulator (CFTR) gene based on nonisotopic SSCP analysis. Because conventional SSCP analysis is often hampered by poor yield of single-stranded DNA, we applied the well-established solid-phase technique in which streptavidin-coated magnetic beads are used to immobilize biotinylated polymerase chain reaction (PCR) products. High yield of single-stranded DNA can be eluted from the solid phase by denaturation and used for SSCP analysis. An additional advantage of this procedure is that the immobilized single strand is available without any further purification steps for solid-phase sequencing.

Base Sequence↗
PubMed1993

[Mutation in the cystic fibrosis transmembrane-regulator gene in bilateral congenital ductus deferens aplasia].

A 28-year-old man and his 27-year-old wife were investigated for infertility of 3 1/2 years' duration. There was azoospermia caused by bilateral aplasia of the vas deferens, and therefore it was planned to aspirate spermatozoa from the epididymis for the purpose of in-vitro fertilisation. As part of the diagnostic workup the man was investigated for those mutations of the cystic fibrosis transmembrane regulator (CFTR) gene which occur with undue frequency in association with aplasia of the vas deferens. Deoxyribonucleic acid (DNA) analysis revealed a typical three base deletion (delta F 508). In the wife, CFTR gene mutations were excluded with 80% probability. The likelihood of cystic fibrosis in this couple's children was accordingly estimated to be about 0.2%--an acceptable risk. Assisted fertilization in patients with bilateral aplasia of the vas deferens should not be undertaken until they have been thoroughly investigated and informed of the risks.

Adult↗
PubMed1993

Hemoglobin E and codon 17 nonsense: two beta-globin gene mutations common in Southeast Asia detected by the use of ARMS.

Hemoglobin E (codon 26 GAG-->AAG) and codon 17 nonsense (AAG-->TAG), two clinically important mutations of the beta-globin gene, are common in Southeast Asia. The detection of these mutations using allele-specific PCR is described. Together with the previously reported method for the detection of the common Southeast asian codon 41-42 frameshift mutation (del CTTT), it is possible to identify the vast majority of clinically important beta-globin gene mutations in Southeast Asian populations by means of nonradioactive methods.

Alleles↗
PubMed1991

A frameshift mutation in exon 2 of the phenylalanine hydroxylase gene linked to RFLP haplotype 1.

A deletion of a single base in codon 55 (exon 2) of the phenylalanine hydroxylase (PAH) gene has been identified by direct DNA sequencing of 94 phenylketonuria (PKU) chromosomes. This mutation alters the reading frame so that a stop signal (TAA) is generated in codon 60 of the PAH gene. Haplotype analysis revealed that all PKU alleles showing the codon 55 frameshift mutation exhibited haplotype 1. In our panel of DNA probes 13% of all mutant haplotype 1 alleles carry this particular mutation. Patients who were compound heterozygotes for this deletion and R408W in exon 12, or the splice mutation in intron 12, were affected by severe PKU. Thus, the clinical data provide additional evidence that haplotype 1 PKU alleles carry molecular defects which confer a null phenotype. In addition, we were able to show that the newly detected mutation occurs on alleles of different ethnic background.

Amino Acid Sequence↗
PubMed1991

Molecular analysis of PKU haplotypes in the population of southern Poland.

Out of a population of 138,598 infants born in southern Poland between 1987 and 1989, and screened for phenylketonuria (PKU), 28 cases were ascertained probands and their parents were isolated and eight polymorphic restriction sites were analyzed within the phenylalanine hydroxylase gene region. Twenty-one different haplotypes (HT) were revealed, five of them representing new categories. The most common haplotypes among those carrying normal alleles were: HT1 (27.3%) and HT4 (11.4%). Within the group of haplotypes with mutant alleles the most frequent was HT2 (56.8%), whereas the frequency of this haplotype in other European populations, such as French, Danish and German, ranged from 12% to 24%. HT3, being the most common in Danish (38%), and relatively frequent in the other western European (13-14%) populations, appeared to be very rare in our sample (2.3%). The mutation of codon 408 (exon 12, C----T, Arg----Trp), which has been described to be tightly linked to HT2, was tested on amplified DNA by dot-blot hybridization. This mutation was found in 25 out of 44 proband chromosomes. In one case it was linked to HT5, in the remaining 24 to HT2. Our results confirm molecular heterogeneity of PKU haplotypes, as well as their significant interpopulation variation.

Alleles↗
PubMed1991

Phenylketonuria in Poland: 66% of PKU alleles are caused by three mutations.

In order to investigate the molecular basis of phenylketonuria (PKU) in the Polish population, we screened 44 mutant chromosomes from PKU probands for six known mutations, frequently occurring in western European countries, by polymerase chain reaction amplification of their genomic DNA and hybridization with allele-specific oligonucleotides. Our results show that the majority (66%) of all PKU alleles are characterized by three different mutations: in codon 408 (56.8%), codon 158 (6.8%) and codon 261 (2.27%). Of the mutant haplotype 2 alleles, 96% were linked to the mutation in codon 408. Out of five mutant haplotype 4 alleles, three showed the codon 158 mutation, and out of four mutant haplotype 1 alleles, one had the codon 261 mutation. In two families, MspI digests revealed an additional 13.5-kb band similar in length to that previously reported. However, analysis of exon 9 excluded the presence of the T to C transition originally described, indicating a new MspI variant in the Polish population.

Alleles↗
PubMed1990

Hb D Los Angeles (D-Punjab) and Hb Presbyterian: analysis of the defect at the DNA level.

Amplification of the beta-globin gene by the polymerase chain reaction (PCR) and direct sequencing were used for a fast and reliable identification of the beta-globin variant Hb D Los Angeles and revealed the predicted G----C substitution in codon 121. The same method showed the molecular defect in Hb Presbyterian to be a C----G substitution in codon 108; this eliminates a MaeII restriction site.

Base Sequence↗
PubMed1990

Classical phenylketonuria in Bulgaria: RFLP haplotypes and frequency of the major mutations.

RFLP haplotypes and common mutations in the phenylalanine hydroxylase gene have been studied in a group of 29 Bulgarian PKU families. Haplotype distribution differs from that in other European populations, with a predominance of haplotypes 2 and 6 and a total absence of haplotype 3. The amino acid substitution in codon 408 is the most frequent molecular defect. The splicing defect in intron 12 is not found in Bulgarian PKU patients. Testing for three mutations, reported to be common among haplotype 1 and 4 alleles, has shown that they occur less frequently in Bulgarian PKU patients. Screening with five pairs of allele specific oligonucleotides failed to show the mutation in 59% of the patients. These findings add to the evidence that PKU is heterogeneous and that significant interpopulation differences exist. At present, DNA data cannot be used as an aid in early clinical classification and prognosis of hyperphenylalaninaemia in Bulgaria.

Bulgaria↗