Biomedical subjects
Publications and source records attributed to J F Mattei.
Explore the source record for details and available documents.
A chromosome make-up of 45X/46XY can be associated with gonadal dysgenesis, partial dwarfism and Turner-like congenital abnormalities according to Simpson's terminology, as can pure 45X. The Turner syndrome in the form of X/XY is rare. There is a double interest in the case that we report apart from its rarity; first because it has been possible to show lack fluorescence of the Y chromosome which can occur in the pathogenesis of clinical manifestations, when a third clone exists as an addition together with a ring chromosome Y. Because the risks of tumours developing are great when the caryotype includes a Y even if it is one with banding the adnexae should be removed routinely in these cases. A tumour can develop in these girls whereas there is practically no risk if the caryotype is 45X or a mosaic without a Y in it.
We studied the quantitative and qualitative variation of associations between acrocentric chromosomes in four subjects on a period of ten months; results show a definite tendency of association in a same subject, tendency which is reproducible and clear. Even though each individual has a determined rate of associations, the number of associated chromosomes and the number of associations themselves do not vary with months. Furthermore, associations do not appear at random; indeed, they have a wide spectrum of variations from one subject to the other but if we take the subjects individually, their associative rate concerning each chromosome do not change with months. Therefore, the phenomenon of association could be viewed as a biological characteristic of each individual.
The authors report the association in a child of monosomy 4p- and tyrosinosis. They discuss the localization of the para-hydroxyphenylpyruvate oxidase locus on the short arm of chromosome 4. They suggest the study of para-hydroxyphenylpyruvate oxidase activity in each child with monosomy 4p-.
Three new cases of partial trisomy of the chromosome 8 short arm are reported. The observations confirm and extend certain clinical, enzyme, and chromosomal data in this type of chromosomal anomaly.
The silver-staining technique was used to study even cases of structural anomalies involving acrocentric chromosomes, excluding Robertsonian translocations. This technique allows identification of breakpoints and furnishes some information about interphase cell dynamics not seen on conventional chromosome preparations.
A pericentric inversion of chromosome 9 was detected in the father of a child with partial trisomy involving the long arms and partial monosomy of the short arms of chromosome 9. A gene dosage effect was demonstrated for adenylate kinase 1 in erythrocytes.
The role of maternal age in chromosomal non-disjunction was investigated by studying 51 families in whom the origin of the meiotic anomaly had been identified. Results of this study were compared with previously published data. This comparison did not show any difference in mean maternal age, nor in distribution of maternal ages when the origin of non-disjunction was maternal, or paternal, or occurred at the first or second meiotic division. These results make questionable the role of maternal age in the birth of Down's syndrome children.
The high incidence of chromosomal anomalies at birth and the severity of the resulting handicap led to examining their detectability by amniocentesis. With current indications for amniocentesis, the detection rate did not excede 30%. Consequently, it seems necessary to estimate the importance of other known risk factors and to calculate the resulting impact this would have on eventually broadening the indications for amniocentesis. A review of the literature led the authors to discuss the relative importance of each known risk factor and its role in public health.
Three children with thrombopenia and radial aplasia were examined at the Centre de Génétique Médicale of Marsielles from 1974 to 1976. In each case the genetic basis of the anomaly was discussed with the family at genetic counseling underlining the high risk of recurrence related to the autosomal recessive transmission. Each proband was the only child of the couple. In the first case the father and mother, each having one child from a previous marriage, decided to have no more children. In the second case, the use of fetoscopy and its limitations were discussed as another pregnancy was desired. However, the parents finally refused the procedure during pregnancy which yielded a second child with phocomelia who did not survive. In the third and most recent case the proband died. Since the young couple strongly desired another child, ultrasonic monitoring of pregnancy was cautiously suggested and its limitations clearly exposed. Echography was regularly repeated from the third month of pregnancy. The forearms were never detected on echography, nor on fetal radiography. Pregnancy was thus interrupted with prostaglandins at 21 weeks gestational age. On examination the fetus presented bilateral aplasia of the forearm. Based on these observations, the authors discuss the problems raised by prenatal diagnosis of upper limb malformations.
Explore the source record for details and available documents.
A woman presented a complex chromosome rearrangement with translocation between chromosome 2 and 4 in addition to an insertion of the band 4q12 leads to q13 in the long arm of chromosome 18. The authors present a case study of the daughter who displayed the abnormal chromosome 18 and trisomy of band 4q12 leads to q13.
Three patients have been detected because of abnormal phenotypes. Balanced chromosome rearrangements were found in their karyotypes, and in one of the parents in each case. In these three families the association of an abnormal phenotype and a balanced chromosome rearrangement may either be a chance happening or be induced by a submicroscopic loss of chromosome material, for which different position effects may be responsible, according to the case in question. These observations prompt us to ask what decision should be made relative to termination of pregnancy if such a rearrangement is found in amniotic cells in a family with a previous abnormal child.
Of 61 families of children with trisomy 21, polymorphism of chromosome 21 elucidating the origin of the extra chromosome was found in 42. Nondisjunction was of paternal origin in 8 cases (19.04%) and the anomaly occurred with equal frequency during the first and second meiotic divisions. Maternal nondisjunction was demonstrated in 34 cases (80.95%), in which nondisjunction occurred by far the most often during the first meiotic division (29 cases). These results are in agreement with data from the literature, and suggest the existence of at least two different causes for chromosomal nondisjunction, the first being the same in both sexes and occurring in both meiotic divisions and the second specifically limited to the first meiotic division in the mother.
The authors studied 17 cases of Robertsonian translocation. In all cases but one C banding showed that a dicentric translocation was involved. Silver staining demonstrated the presence of an NOR between the two centromeres in only one case.
Erythrocyte superoxide dismutase is a cuproprotein displaying increased activity in cases of trisomy 21. In this study, the three erythrocyte copper fractions were compared at constant serum copper levels in children with and without trisomy 21. The labile erythrocyte copper level was found to be identical in both groups of children. Total erythrocyte copper, especially the stable fraction, was increased in cases of trisomy 21. The approximately fifty per cent ob served increase correlates with the augmented superoxide dismutase activity related to the presence of an extra chromosome 21. Measurement of the stable erythrocyte copper fraction could constitute an indirect method for evaluating superoxide dismutase activity.
Dermal patterns in a group of Down's syndrome patients, a normal control population and a group of parents of Down's syndrome patients were studied in an attempt to identify an Index Score to be used in differentiating controls from parents of Down's syndrome children. Using only three patterns (simian crease, palmar hypothenar pattern and Cummins' Index), a parents' Index Score was established which correctly diagnosed 80.83% of controls and 79.17% of parents. The predictive value of this index and its interest in genetic counselling are discussed.
We report the case of a 2-year-old girl who had signs of Duchenne type muscular dystrophy on clinical, electromyographic, laboratory, and pathological examination. The parents of the child are first cousins. A brother and nephew of the mother also had Duchenne type muscular dystrophy. Karyotype analysis in the proband showed both X chromosomes to be morphologically normal. The mother had very high plasma CK levels, equivalent to those observed in carriers of the disease. We discuss different hypothetical mechanisms designed to account for the family pedigree.