Prenatal diagnosis of fragile x syndrome: (cgg)n expansion and methylation of chorionic villus samples

Fragile X syndrome is the most common form of inherited mental retardation, due to an expansion of the (CGG)_n trinucleotide repeat in the FMR-1 gene and hypermethylation of its 5′ upstream CpG island. Two major problems remain to be resolved for fragile X prenatal diagnosis: the abnormal methylation patterns of chorionic villus samples (CVS) and the inability to predict the mental status of females with the full mutation. We present here the results of ten prenatal diagnoses of fragile X syndrome using Southern blotting and polymerase chain reaction (PCR) amplification, and the analysis of 50 further CVS to test the methylation status of the CpG island of the FMR-1 gene. In the ten ‘at-risk’ CVS, eight normal (five males and three females) and two affected male fetuses were detected. Absence of methylation in the CVS was observed in two cases, which was not found upon subsequent examination of the newborn or of fetal tissues. In the 50 CVS not ‘at risk’ for fragile X syndrome, abnormal fragment patterns for probe StB12.3 were detected in 32 per cent for female and 24 per cent for male fetuses. This abnormal pattern could be due to absent or partial methylation of the CpG island of the FMR-1 gene in chorionic villus tissues.     

Digeorge syndrome with total monosomy 22 diagnosed prenatally

A case of monosomy 22 diagnosed prenatally is reported. During pregnancy, ultrasonic observations already revealed several cardiac malformations of the fetus in the 25th week. Following counselling, the pregnancy was terminated. Fetal autopsy revealed several abnormalities associated with DiGeorge syndrome.     

Normal blood cell values in the early mid-trimester fetus

Samples of pure fetal blood from 116 fetuses of 15–21 weeks' gestation were obtained by direct vision fetoscopy. Ninety nine of these fetuses, presumed to be haematologically normal, were suitable for analysis. The data obtained show that the erythropoietic system is evolving rapidly in this gestational age range. The myeloid series shows no significant increase or decrease in numbers apart from eosinophils and basophils which increase significantly with gestational age whereas the platelet count remains constant. The growing application of fetoscopic blood sampling to the prenatal diagnosis and management of fetal blood disorders renders mandatory a knowledge of normal fetal blood values.     

Interpreting countryside recreation: The urban - rural dichotomy

Summary Noting a paucity of sociological research investigating countryside recreation from an experiential perspective, this paper reports on a study aimed at exploring the meaning of such terms as the countryside, rural and natural as they are understood by the person-in-the-street. A typification of countryside recreation is constructed which suggests that individuals have an essentially simple understanding of the environment in this context which centres upon an urban-rural dichotomy. The urban setting is generally associated with negative experiences while the rural setting is regarded more positively. These attitudes suggest that the countryside represents a form of refuge from many stresses commonly associated with modern, urban lifestyles. An implication of this conclusion is that attempts to educate people into recognizing the links between their everyday behaviour and the degradation of the countryside will be met with considerable resistance since this would entail them in reconstruing their relationship with the environment.     

The rhetoric of participation re-examined: The state,NGOs and water users at Varanasi,Uttar Pradesh,India

Summary People's participation is usually regarded as a sine qua non for the success and sustainability of development projects. Yet in practice, it raises a number of questions. Who are the people? Why is their participation sought, and how or at what level, is such participation desired? This paper seeks to examine the rhetoric of participation in the implementation of the Ganga Action Plan (GAP) at Varanasi, in the north-eastern State of Uttar Pradesh, India. Launched in 1985, the GAP is the first major attempt to systematically control and monitor the pollution of a significant river in the country. In addition, it claimed to be a people's programme because of the powerful and deep-seated cultural and religious meaning associated with the Ganga. Varanasi, however, is indicative of its failure to deliver this promise — the GAP is only acceptable to authority because it does not challenge the existing institutional order, and its participatory content is symbolic rather than substantive. Non-govemental organisations, traditionally viewed as intermediary actors between the micro and macro levels, work within the socio-political framework of the city. In the process, water-user groups such as the washermen who derive an economic livelihood from washing clothes in the Ganga, are literally excluded from the definition and process of participation.She obtained her PhD, the basis of the current research, at the University of Cambridge, UK.     

Amniotic alpha-fetoprotein in the prenatal diagnosis of congenital nephrotic syndrome of the finnish type

Congenital nephrosis of the Finnish type (CNF) is rare outside Finland, where the incidence may be as high as 1 in 2000 live births. Neonates with the disorder develop renal failure within the first months of life and without renal transplantation, the prognosis is extremely poor. This case report describes a woman's three pregnancies, two of which were affected with CNF.     

Uniparental isodisomy for chromosome 16 in a growth-retarded infant with congenital heart disease

We report a growth-retarded infant with congenital heart disease and maternal isodisomy for chromosome 16. Non-mosaic trisomy 16 was detected at mid-trimester chorionic villus sampling, performed because biochemical screening indicated an increased Down's syndrome risk. Further karyotyping analysis of the placenta, after delivery, showed a 50 per cent mosaic trisomy 16. The infant had an atrioventricular (A-V) canal defect, scoliosis, and several minor dysmorphic features. Although uniparental disomy for chromosome 16 has been reported previously, to our knowledge this is the first case of uniparental isodisomy for chromosome 16 which has been investigated with multiple DNA probes.     

Early prenatal diagnosis of genetic microcephaly

We report a new case of prenatal diagnosis of recessive microcephaly by ultrasound examination allowing termination of pregnancy at 25 weeks gestation.