摘要:

During a 17‐year period (1971–1988), the Marfan syndrome was diagnosed in 66 patients seen through the Department of Human Genetics, Medical School, University of Cape Town. Following reappraisal and application of the Pyeritz criteria, this diagnosis was confirmed in 33. Of the others, 17 with tall stature and a Marfanoid habitus had insufficient additional manifestations for firm diagnosis and were eliminated from the series. Sixteen had Marfanoid habitus, tall stature, arachnodactyly and other abnormalities which might have indicated the presence of a different syndrome. The difficulty in making a clinical diagnosis of the Marfan syndrome is stressed and emphasizes the need for a biomolecular mar

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03524.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

A mother and daughter with an interstitial deletion of the chromosome segment 21q11 to 21q2l.3 have similar minor dysmorphism and mild mental retardation. These two patients are compared to others in the literature with deletion of the same region of chromosome 21. Molecular analysis of DNA from our patients localizes the DNA segments D21S1, D21S11, D21S8, and D21S22 within the deleted region.

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03525.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Monozygotic twin sisters from Qatar, concordant for the Rubinstein‐Taybi syndrome, are described. Skeletal anomalies not previously seen in this syndrome are described. The mode of inheritance is reviewe

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03526.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Plasma from 158 presumed healthy nuclear families has been analyzed by high‐resolution, two‐dimensional electrophoresis to study the frequency and effects of the genetic polymorphism in human apolipoprotein A‐IV. Two common alleles, apo A‐IV 1 and apo A‐IV 2 were detected with relative frequencies of 0.943 and 0.057, respectively. Autosomal codominant transmission of these two alleles coded for by a single structural locus was demonstrated. Furthermore, we studied the effects of this apo A‐IV variability on total plasma cholesterol, triglyceride, glucose levels and gamma‐glutamyltransferase activity. Statistically significant differences among apo A‐IV genotypes for the average glucose level were detected. The average effect of the apo A‐IV 1 allele was to lower plasma glucose levels by 0.013 mmol/l, whereas the average effect of the apo A‐IV 2 allele was to raise glucose lev

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03527.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

A total of 295 patients, parents and unaffected sibs from 106 CF‐families in central and northeastern Switzerland were investigated with probes 7C22(D7S16), metH, metD, pKM19, pXV‐2c and pJ3.11(D7S8) for eight DNA polymorphisms (RFLP's). Linkage disequilibrium to the CF locus and haplotype frequencies were compared to those in other populations. They are comparable to other Caucasian populations and, for pKM 19 and pXV‐2c, very close to the findings in Italy. The prevalence of certain haplotypes among the CF and the normal allele‐bearing chromosomes indicate that the majority of the CF cases are probably the result of one ancient mutation in a common ancestor, but that there may be allelic heterogeneity accounting for an important proportion of patients, that may differ between countries or regions. Informative family constellations for the different polymorphisms in Switzerland and strategies for carrier detection and prenatal diagnosis are discussed. Haplotype analyses for each country and its ethnic subgroups are reco

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03528.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

We present here an alternative approach to the study of mosaic cell lines containing dicentric chromosomes. The approach is based on chromosome‐specific non‐radioactivein situhybridization with centromere (alpha satellite DNA) probes. The hybridization analysis may be used as an alternative to theC‐band analysis, while at the same time to some extent replacing the Q‐band analysis as well. The advantage of usingin situhybridization is mainly that it allows the very fast screening of a large number of metaphases. We illustrate this new application of the technique by using it for the analysis of two cases of isodicentric X‐chromosomes. The approach is expected to be generally applicable, so that it may be applied to the scoring of other types of chromosomal mosaicis

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03529.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

DNA from 164 unrelated Duchenne muscular dystrophy patients was screened with cDNA probes from the dystrophin gene. Molecular deletions were demonstrated in 82 (50%) subjects. Sixty‐two deletions (76%) were detected using cDNA probes Cf56a (cDNA 8) and Cf56b (cDNA 6–7) which map to the centre of the gene, while 22 deletions (27%) mapped to the 5′ end of the gene. In three subjects, the deletion extended from the 5′ end to the centre of the gene. One deletion was identified by probe 47–4 (cDNA 5b‐7) alone. In six of the deletions, junction fragments of altered size were observed. Using the three cDNA probes, RW2kb, Cf56a (cDNA 8) and Cf56b (cDNA 6–7), 99% of the deletions were detected. This will have implications for prenatal diagnosis in deletion families. Unlike Becker muscular dystrophy, where the deletions are more homogeneous, the deletions in the present study were heterogeneous both in size and position. No correlation between intelligence and either site or extent of delet

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03530.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

To test the hypothesis of reduced chiasma frequency causing nondisjunction during meiosis, we examined 34 Down syndrome patients and their parents. Chromosomal polymorphisms and RFLP markers were used to trace the parental origin as well as the frequency of recombination of chromosomes 21. In all but one case, the parental origin and the meiotic stage of nondisjunction could be established by either technique. In 11 cases recombination could be deduced to have taken place during meiosis in the parent who contributed the extra chromosome 21. Because of the underestimation which is inherent in the methods used, these results do not seem to support the chiasma theory.

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03531.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Rare chromosomal fragile sites may adversely affect specific alkies of closely linked genes when in cis‐configuration. This is illustrated by data published in Sutherland&Hecht (1985) on chromosome 16 at band q22.

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03532.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

A restriction site polymorphism in the Lp(a) apoliprotein gene (the LPA gene) is reported. The basis for the polymorphism is presence or absence of an MspI restriction site that appears to be 3‘ to the last kringle IV structure of the gene. The “1” gene (presence of the restriction site) has a frequency of 0.316 and the “2” gene (absence of the restriction site) has a frequency of 0.684. Both members of each of 67 monozygotic (MZ) twin pairs had the same genotype and there was Mendelian segregation of the DNA variants in 40 families with a total of 75 children. There was a lower proportion of people with genotype 1–1 in the top quartile than in the 3 bottom quartiles of the population distribution of Lp(a) lipoprotein levels but the difference did not reach statistical s

ISSN:0009-9163    

DOI:10.1111/j.1399-0004.1990.tb03533.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY