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In the 1950s with the identification of the presence of a Barr body in amniocytes for fetal sexing in X-linked disorders, prenatal diagnosis became a reality. Rapid development followed and within a decade fetal diagnosis by transabdominal amniocentesis had expanded to include the prenatal diagnosis of chromosomal abnormalities, of inborn errors of metabolism and of neural tube defects. A similar revolution has taken place in the past decade with the development of techniques for sampling chorion for fetal diagnosis. ‘Chorionic Villus Sampling, Fetal Diagnosis of Genetic Disease in the First Trimester’ offers the reader up-to-date information on all aspects of chorionic villus sampling, including the timing of the biopsy, the techniques of sampling, the fetal and maternal risks associated with the procedure, the genetic disorders in which the techniques may be used, and the reliability of results. There are sixteen chapters which deal with the techniques and risk of chorionic villus sampling, laboratory aspects of fetal diagnosis and social and ethical considerations. A primary aspect of chorionic villus sampling which must be considered before the technique can be used in the preventive genetic services, is the risk involved to both the mother and the fetus. There are four chapters which comprehensively bring together studies throughout the world. Although definitive answers to the size of the risks must await trials, all the authors agree that there should be a cautious introduction of chorionic villus sampling into clinical service. There are six chapters covering the laboratory examination of the biopsy including advantages and disadvantages of direct and culture methods of fetal karyotyping, biochemical and enzyme analysis. The use of recombinant DNA technology has an increasingly important role in fetal diagnosis. The excellent chapter by Old discusses the use of DNA techniques in the fetal diagnosis of the haemoglobinopathies, a topic which also is dealt with in the chapters on sickle cell anaemia and thalassaemia. There is a paucity of information on the use of chorionic villus sampling and DNA technology in the fetal diagnosis of disorders such as Duchenne muscular dystrophy, haemophilia and cystic fibrosis, which are likely to preponderate numerically in the United Kingdom. In the first chapter entitled ‘Introduction and Historical Perspectives’, Modell states that the ‘most important factors influencing the development of fetal diagnosis are not technical but social, namely the changing complex pattern of attitudes to the control of human reproduction’. She returns to this theme in the penultimate chapter entitled ‘Some Social Implications of Early Fetal Diagnosis’. These are two excellent chapters and should be carefully read by all involved in the clinical application of preventive genetic services. Doctors can no longer avoid the obligation to follow through on the consequences of new developments. Immediately a disorder becomes diagnosable by fetal techniques, that disorder becomes avoidable in principle. There are many lessons to be learnt from the past experiences with fetal diagnosis by amniocentesis. Probably the most important one is the fact that preventive genetic services are delivered very inefficiently to the community. For mothers to take advantage of the new technique of chorionic villus sampling, they will need to have some idea of their potential risk before conception. Thus, there is need for a public health education programme. This book is highly recommended to medical geneticists, obstetricians, paediatricians, cytogeneticists, molecular biologists, other laboratory workers and others who need to keep apace with developments in chorionic villus sampling, NORMAN C. NEVIN | ||||||