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Some multisystemic abnormalities associations which can be found by ultrasound examination are sometimes chromosome anomalies and amniocentesis must be performed for confirmation. By ultrasonography we can now reach a new objective element: the fetus extremities. Limbs anomalies, such as polydactily, club-feet and/or club-hands must lead to perform amniocentesis in order to assess or not a possible 13 or 18 trisomy.

The analysis of DNA repair processes is described in two pregnancies at risk for xeroderma pigmentosum. In both cases, excision repair (measured by unscheduled DNA synthesis) and postreplication repair were analyzed. An affected and an unaffected fetus were identified within 3 weeks after amniocentesis. The cells from the affected fetus were found to be deficient in excision DNA repair, whereas the PRR patterns were intermediate between those of normal and PRR deficient cells. This indicates the possibility of prenatal diagnosis of PRR deficient XP patients (XP variants).

Chorionic villi biopsy allows first trimester prenatal diagnosis of some genetic diseases. In this study the results of 163 diagnoses are presented, and among these, 59 diagnoses of autosomal recessive metabolic diseases with 8 observations of congenital adrenal hyperplasia due to 21 OH deficiency and 6 observations of Fanconi anemia.

Associations of the three n degrees 18 chromosomes were studied in a trisomy 18 fetus (the chromosomal constitution of which had been identified by amniocentesis). The three classes of associations observed were those observed in other trisomic organisms:trivalent, trivalent presenting an important asynaptic region, and bivalent accompanied by a univalent. In addition, the sequence was established of chromomeres, the number of which varied from 18 to 23 depending on the degree of chromosome contraction. In elongated pachytene oocyte bivalents each G-band of mitotic metaphase chromosomes could be subdivided into several sub-bands.

Fifteen cell lines initiated from embryonic tissues of abortuses with C trisomy were frozen and stored. They were thawed and karyotyped again with banding techniques. Trisomies 7, 8, 9, 10, and 12 were identified. Some characteristics of these abortuses are discussed in connection with the chromosome identifications.

This article, which is the second installment of a study of the psychological aspects of antenatal diagnosis, presents the analysis of interviews with women (and with some of their partners) who were examined because of their age. The characteristics of these "late" pregnancies seem to be the following: 1. The question of a abnormality shifts the emphasis from the child to the pregnancy itself, which is often lived through as something abnormal; 2. knowing the sex of the child before its birth emphasizes the abnormality of the pregnancy and therefore draws attention to the problem of the age of the mother; 3. this last chance of pregnancy emphasizes the question, which is near in time for these women, of the menopause, of getting old and of death; 4. it also emphasizes in a most emphatic way the question of mourning, of loss, of the place of the future child in the history of the woman and in a more general way the question of the desire to have a baby.

Meconium ileus was the presenting feature of cystic fibrosis in 46 per cent of the couples which have been referred for prenatal diagnosis. In fetuses which have been aborted on the basis of alkaline phosphatase isoenzymes assays, meconium ileus represented the only pathological feature of cystic fibrosis, and was observed in three fourths of the cases. Real-time sonographic examination of fetuses at the time of amniocentesis was able to show an echogenic mass in the abdomen corresponding to the meconium ileus, and thus may afford a complementary means of diagnosis.

Meiotic studies were made on the fetal ovaries of a triploid fetus, 69,XXX. The association modalities of the three chromosomes in human triploidy are the same as those described in several plant species; i.e., trivalents, bivalents and univalents can be found in the same nucleus. In most cases of trivalent configuration, the association occurs between pairs.

A pericentric inversion of chromosome 9 has been detected in 10 unrelated families. The break points are identical and the inversions involved the heterochromatic segment. The effects of inversion of chromosome 9 on different aspects of reproductive failure are discussed.

In three cases of triploïdy, the origin of extra haploid set is found by chromosomal and HLA markers. It does not confirm a relationship between paternal origin and partial hydatidiform mole. In case of prenatally diagnosed triploïdy, a protocol for biological studies is suggested.

We have monitored 3 pregnancies at risk for galactosemia by deficiency in Galactose-1-Phospho uridyl transferase. Galactosemia was diagnosed in the 1st case; heterozygoty in the 2nd, and a "double heterozygoty" in the 3rd. The latter is the first example of such a diagnosis. Post natal confirmation was obtained in the three cases. Arguments are given for the usefulness of this prenatal diagnosis.

The results confirmed the fiability and the accuracy of the different acts and technics leading to these diagnosis. A prospective study of the safety of amniocentesis involved more than 1000 subjects. The analysis of the information on the pregnancy, the delivery, the state at birth and after birth of the infant did not show any significant increase of pathologic findings which may be related to immediate or delayed consequences of amniocentesis.

The activity of 13 cytoplasmic enzymes has been determined in fibroblast extracts from 9 triploid and 13 control lines. The results show a high activity for 2 X-linked enzymes, glucose 6-phosphate dehydrogenase and phosphoglycerate kinase. These data, together with cytogenetic observations, support the contention that 2 X chromosomes were active in the triploid lines.

Interferon sensitivity of different normal and aneusomic human cells and of different mouse-human hybrids cells has been compared. G21 trisomic cells are more sensitive than diploid cells; whereas, on the contrary, triploid cells are normal in their human interferon sensitivity. Among other aneusomic cell lines tested, E16 trisomic cells are significantly less sensitive. These data are in favor of the hypotheses that the G21 chromosome carries genetic information for structural proteins involved in the receptor system for interferon, that there is a regulatory mechanism governing the antiviral state, and that the E16 chromosome is a possible candidate for carrying information for such a depressive regulatory mechanism. None of the chromosome abnormalities studies are involved with interferon synthesis.

Epidemiologic studies, retrospective and prospective, were done on 1500 abortions collected from 1966-1972. No secular or seasonal variations were observed. From the analysis of the relative frequencies of the different types of chromsome anomalies it is estimated that 1 out of every 2 conceptions has a chromosome anomaly. Maternal-age influence was found only for the autosomal trisomy group, mainly D and G trisomies. No effect of oral contraceptives were discovered. An increased frequency of chromosome anomalies occurred after ovulation-inducing therapy and after occupational exposure of the father to irradiation. No variations in the fertility rate and in the frequency of congenital malformations in births following abortions was noted. The incidence of recurring abortion was mainly influenced by the reproductive history of the couple before the karyotyped abortion.

Argininosuccinate synthetase activity was measured in amniotic fluid cells cultured from 25 normal fetuses and from 2 fetuses at risk for citrullinemia. Among the 25 control lines, argininosuccinate synthetase was low in epithelial-like cultures and high in more fibroblast-like cultures. The radioactivity incorporated from 14C-citrulline into protein was proportional to argininosuccinate synthetase activity. The activity of argininosuccinate lyase, the next enzyme in the urea cycle, was unaffected by a predominance of one or the other cell type. Argininosuccinate synthetase was low but detectable in cells from the two fetuses at risk for citrullinemia. The pregnancies were continued and both resulted in clinically normal females. Thus factors such as predominant cell type may affect area cycle enzyme activity in cultured amniotic fluid cells and should be taken into consideration in attempts to diagnose citrullinemia prenatally.

The enzymatic activities of gamma-glutamyl-transpeptidase and of aminopeptidase M have been determined in amniotic fluids taken in pregnancies with a trisomic conceptus. The low values obtained in these fluids may be the consequence of fetal growth retardation.

Among 5315 prenatal diagnoses performed for various indications (maternal age, neural tube defect, metabolic diseases, X-linked diseases, pathologic pregnancies) 29 unexpected structural chromosome rearrangements were found in fetal cells. Fourteen were de novo chromosome rearrangements, six unbalanced, and eight balanced. Fifteen were inherited and balanced rearrangements. This high frequency of structural anomalies is discussed.

A systematic study of microvillar enzyme activities in the amniotic fluid in correlation with their values in different fetal tissues during development has been undertaken. Microvillar enzymes appeared in the amniotic fluid at the time of disappearance of the anal membrane, 12-13 weeks, and declined from the 18th week until the 24th week. The study of fetal tissues and fluids has shown that gamma-glutamyltranspeptidase is mainly of liver origin. The significant decrease of the activities of these amniotic fluid enzymes has been the basis of prenatal diagnosis of cystic fibrosis. These assays may be useful for the diagnosis of certain digestive tract abnormalities at later stages of pregnancy.

Chromosome anomalies are often found in ova expelled spontaneously. The proportion of ova affected varies with the sampling conditions. A great variety of anomalies were distinguished. The authors studied in turn : monosomies, trisomies, polyploid types double aberrations, mosaics, and structural anomalies. The frequency of the anomalies was studied in relation to the duration of the pregnancy and the duration of the development of the ovum. Among the factors studied, maternal age was correlated only with the cases of trisomy. The age of the gametes seemed to be of great importance. It was difficult to determine the effect of oral contraceptives but they did not seem to be important. In contrast, ovulation inducers were implicated. As regards to the effects of irridiation, the incidence of anomalies appeared to be increased by radiography before pregnancy and by irradiation to which the husband was exposed at his place of work. The previous obstetric history makes it possible, to a certain extent, to forecast the risk of genetic abortion and it is possible to calculate statistically that the number of anomalous embryos conceived is practically identical to the number of normal infants born.