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E Passarge

Publications and source records attributed to E Passarge.

162 records · Page 9Linked to original sources
PubMedDate not supplied

Differential expression of fragile site Xq27 in cultured fibroblasts from hemizygotes and heterozygotes and its implications for prenatal diagnosis.

Expression of the fragile site Xq27 (fraXq27) was studied in metaphases derived from fibroblasts of 8 hemizygotes and 2 heterozygotes, cultured in 2 different media containing reduced concentrations of folic acid. The proportion of fra(X) (q27)-positive metaphases ranged from 1.0 to 14%, which is considerably lower than in lymphocyte cultures from the same individual, but differed with respect to the culture medium used. Four hemizygotes showed a higher proportion of fra(X)-positive cells in medium 199 than in methotrexate-exposed cultures. No fra(X)-negative cultures were observed when the folic acid inhibitor methotrexate was added to medium 199. Thus, in all 10 individuals carrying the fra(X), the fragile site could be detected in fibroblast cultures. We conclude that the expression of fra(X) (q27) in cultured fibroblasts should be studied using at least 2 types of culture conditions, because familial, i.e. genetic differences may influence the expression of this fragile site in fibroblasts. The implications for prenatal diagnosis are discussed on the basis of investigations in 15 pregnancies at risk for the trait.

Adolescent↗
PubMedDate not supplied

Origin of nondisjunction in trisomy 8 and trisomy 8 mosaicism.

Causes of chromosomal nondisjunction is one of the remaining unanswered questions in human genetics. In order to increase our understanding of the mechanisms underlying nondisjunction we have performed a molecular study on trisomy 8 and trisomy 8 mosaicism. We report the results on analyses of 26 probands (and parents) using 19 microsatellite DNA markers mapping along the length of chromosome 8. The 26 cases represented 20 live births, four spontaneous abortions, and two prenatal diagnoses (CVS). The results of the nondisjunction studies show that 20 cases (13 maternal, 7 paternal) were probably due to mitotic (postzygotic) duplication as reduction to homozygosity of all informative markers was observed and as no third allele was ever detected. Only two cases from spontaneous abortions were due to maternal meiotic nondisjunction. In four cases we were not able to detect the extra chromosome due to a low level of mosaicism. These results are in contrast to the common autosomal trisomies (including mosaics), where the majority of cases are due to errors in maternal meiosis.

Child↗
PubMedDate not supplied

[Congenital contractural arachnodactyly (CCA syndrome)--an autosomal dominant hereditary connective tissue disease].

Congenital contractural arachnodactyly (CCA syndrome) is an autosomal dominant connective tissue disease which must be distinguished in particular from Marfans' syndrome and the heterogeneous arthrogryposis multiplex congenita. The principal symptoms are multiple congenital contractures with a quite pronounced tendency to regression, scoliosis, dolichostenomelia and arachnodactyly, and malformation of the auricles. The authors report on a young woman (the proposita) and her son, who are typically affected. Observation of the course in these two patients confirms the rule that the condition has a relatively favorable prognosis. The mother of the proposita suffered from dolichostenomelia and arachnodactyly, while congenital contractures and dysmorphous auricles were absent; this could represent a--still hypothetical--mild form of the syndrome. The symptomatology, differential diagnosis, treatment and genetics of the CCA syndrome are discussed in detail with reference to a further 33 cases in the literature.

Adult↗
PubMedDate not supplied

[Clinical, endocrinological, histological and chromosomal investigations on Klinefelter's syndrome].

In a clinical study 101 patients with Klinefelter's syndrome (Kl. sy.) are evaluated. Clinical, endocrinological and histometrical aspects were of main interest. The results were compared with a group of patients with azoospermia by obstruction. The statistical evaluation showed significant differences concerning body-height, volume of ejaculate, size of testis, and the concentration of FSH and LH in serum. Histometrical investigations showed significant differences for the diameter of seminiferous tubules and their wall-thickness. The various degrees of Leydig-cell-increase at Kl. Sy. are described as--increased--excessively increased--and adenomalike. Sex-Chromatin was found positive in 62 of 64 cases of Klinefelter's syndrome, verified by chromosome analysis. The number of Barr-bodies ranged from 1-45 (200 cells evaluated) x mean was 9,6. The analysis of chromosomes in 64 cases showed a karyotype of 47,XXY in 59 cases, a 46, XY/47,XXY mosaic in 4 cases and 46,XX/46,XY/47,XXY mosaic in 1 case. The discussion pointed out, that Kl. sy. has no typical, but a variety of symptoms. The position of the evaluation of sex-chromatin for diagnosis and the possibilities of errors are discussed. The problem of fertility in Kl. sy. is mentioned, as we found two cases with complete spermatogenesis, yet with azoospermia, among our patients. The pathogenesis of the characteristical histological changes in testis with Kl. sy. remains open. The mechanism which may lead to the striking increase of Leydig-cells is discussed.

Adolescent↗