These two volumes record the scientific and clinical work presented at the VIIth International and 3rd European joint symposium on purine and pyrimidine metabolism in man held at the Bournemouth International Conference Centre, Bournemouth, UK, from 30th June to 5th July 1991. The series of international meetings at three yearly intervals have previously been held initially in 1973 in Israel, then Austria, Spain, the Netherlands, USA and Japan. The European society for the Study of Purine and Pyrimidine Metabolism in Man (ESSPPM) which has its own executive and some finance first met in Switzerland in 1987, then in Germany in 1989. The steady evolution of the science in this series of meetings is intellectually satisfying; the subsequent clinical progress is emotionally and economically reassuring. As befits the position of purines and pyrimidines at the centre of biochemistry, there has been steady scientific development into molecular genetics and now onto developmental controls and biochemical pharmacology. The complexities of the immune system are being unravelled but an understanding of the human brain largely eludes us. Laboratory based scientists now predominate over those who work as clinical specialists in vii rheumatology, immunology, oncology and paediatrics. However, there continue to be major clinical objectives since large sections are concerned with major causes of death like ATP depletion, cancer and now AIDS; the laboratory work is providing clinical solutions.

captured for the published proceedings. Nevertheless, the two Supplements to this Journal (also available together as a hard-backed book) do, over the years, embrace many of the major aspects of the study of inborn errors of metabolism and can, particularly with the Short Communications section, be used as a way into the literature on specific new topics. We hope that with judicious selection of material these supplements will continue to provide, as did the Society's earlier annual publications, a balanced record of the present state of the subject in all its facets, a record of interest to those working in allied fields as well as to the specialist. R. J. Pollitt G. M. Addison R. A. Harkness The papers listed below were also presented at the meeting. Scripts were not available by the time of publication. 1. Tangier disease and related disorders of apolipoprotein Al. G. Assmann, Munster. 2. Contribution to Ethics Symposium by M. E. Pembrey, London.

These two volumes record the scientific and clinical work presented at the VIIth International and 3rd European joint symposium on purine and pyrimidine metabolism in man held at the Bournemouth International Conference Centre, Bournemouth, UK, from 30th June to 5th July 1991. The series of international meetings at three yearly intervals have previously been held initially in 1973 in Israel, then Austria, Spain, the Netherlands, USA and Japan. The European society for the Study of Purine and Pyrimidine Metabolism in Man (ESSPPM) which has its own executive and some finance first met in Switzerland in 1987, then in Germany in 1989. The steady evolution of the science in this series of meetings is intellectually satisfying; the subsequent clinical progress is emotionally and economically reassuring. As befits the position of purines and pyrimidines at the centre of biochemistry, there has been steady scientific development into molecular genetics and now onto developmental controls and biochemical pharmacology. The complexities of the immune system are being unravelled but an understanding of the human brain largely eludes us. Laboratory based scientists now predominate over those who work as clinical specialists in vii rheumatology, immunology, oncology and paediatrics. However, there continue to be major clinical objectives since large sections are concerned with major causes of death like ATP depletion, cancer and now AIDS; the laboratory work is providing clinical solutions.

These two volumes record the scientific and clinical work presented at the VIIth International and 3rd European joint symposium on purine and pyrimidine metabolism in man held at the Bournemouth International Conference Centre, Bournemouth, UK, from 30th June to 5th July 1991. The series of international meetings at three yearly intervals have previously been held initially in 1973 in Israel, then Austria, Spain, the Netherlands, USA and Japan. The European Society for the Study of Purine and pyrimidine Metabolism in Man (ESSPPM) which has its own executive and some finance first met in switzerland in 1987, then in Germany in 1989. The steady evolution of the science in this series of meetings is intellectually satisfying; the subsequent clinical progress is emotionally and economically reassuring. As befits the position of purines and pyrimidines at the centre of biochemistry, there has been steady scientific development into molecular genetics and now onto developmental controls and biochemical pharmacology. The complexities of the immune system are being unravelled but an understanding of the human brain largely eludes us. Laboratory based scientists now predominate over those who work as clinical specialists in VIi rheumatology, immunology, oncology and paediatrics. However, there continue to be major clinical objectives since large sections are concerned with major causes of death like ATP depletion, cancer and now AIDS; the laboratory work is providing clinical solutions.

With improved control of most environmental causes of disease, genetic illness has assumed a primary importance in the causation of handicap and mortality in all age groups. At present, effective therapy is available for relatively few genetic conditions and prenatal diagnosis is an important option for couples at high risk. The task of providing prenatal diagnosis for these couples requires a team approach between clinicians and scientists, and is complicated by the large number of diverse conditions and by the rapid developments in the field, both obstetric in relation to imaging and tissue sampling methods and genetic in relation to techniques for analysis. Against this background, the aim of the Symposium was to provide an overview of the current status of prenatal and perinatal diagnosis of inborn errors of metabolism. The format consisted of the usual mixture of specific invited overviews and free communications in either oral or poster form. The invited overviews, as can be seen from this publication, covered a wide range, from accepted methods for neonatal diagnosis and screening to newer techniques for prenatal diagnosis and likely future developments with respect to gene therapy. Similarly, the oral com munications included reviews of experience with biochemical analysis of chorionic villus sampling from major centres, more specific examples of progress towards the basic defect in Batten's disease and Canavan's disease, and prospects for effective therapy in Menkes' disease and a lipid myopathy."

The articles in Issue 4 of JOURNAL OF INHERITED METABOLIC DISEASE, Volume 16 (1993) contain the main lectures presented at the 30th Annual Symposium of the Society for the Study of Inborn Errors of Metabolism (SSIEM), Leuven, Belgium, 1992, which was dedicated to Inherited Metabolic Diseases and the Brain'. Topics discussed included: Inborn errors and brain fluids, neurotransmitter disorders, inborn errors and demyelination, and recent developments. Participants from many countries provided a state-of-the-art review which will be of interest to clinicians and research workers alike in many different disciplines.

394 finding by Dr C. Jakobs, Amsterdam, was elevated plasma galactitol and/or sorbitol levels in some cataract patients with quite normal activities of the galactose-degrading enzymes and sorbitol dehydrogenase in RBC. Inherited disorders of glycoprotein metabolism were reviewed by Dr M. Cantz, Heidelberg, followed by detailed presentations on selected disorders. The meeting was closed by two exciting lectures, given by Dr J. R. Hobbs, London, and Dr F. Ledley, Houston, on the outcome of bone marrow transplantation and on future aspects of gene therapy in patients with inborn errors of metabolism. Each year the 'Mini' Symposium preceding the main topics attracts increasing numbers and in Munich more than half of the 281 active participants also attended on "Maternal Phenylketonuria," organized by Dr the highly interesting workshop D. Brenton, London. This four-hour workshop included international practical experiences in the treatment of maternal phenylketonuria as well as the results of amino acid transport and animal experiments.

Proceedings of the 24th Annual Symposium of the SSIEM held in Amersfoort, the Netherlands, September 1986.

together with short communications from members to In 1972 the 10th Annual Symposium of the Society for the provide a valuable overview of the current status of this Study ofInborn Errors of Metabolism was held in Cardiff field. The difficulty in establishing an uneq uivocal clinical and the proceedings published in 1973. The meeting was devoted to the treatment of inborn errors of metabolism; response to vitamin treatment was discussed by Dr in particular the dietary treatment of phenylketonuria Leonard. The papers on biotin-responsive combined and vitamin responsive disorders were reviewed. These carboxylase deficiency presented by Drs Bartlett, Wolf two areas have seen notable advances in the intervening and Baumgartner emphasized the widely differing years. It has become apparent that a number of variants of mechanisms which may underline apparently similar PKU are due to defective cofactor metabolism, and, clinical responses. In particular biotinidase deficiency appears to be a unique defect of cofactor recycling. indeed, some patients refractory to simple dietary restriction of phenylalanine respond to the adminis- Riboflavin, thiamine, and pyridoxine responsive disor- tration of the phenylalanine hydroxylase cofactor ders were succinctly reviewed by Drs Gregersen, Duran and Fowler, again interspersed with relevant short biopterin or related compounds. Biopterin, normally communications from members. Two papers by Drs synthesized de 110W, in some individuals has become a *vitamin'.

The use of cultured cells in the clinical diagnosis of hereditary metabolic dis ease is a rapidly developing subject to which many different disciplines have brought their expertise and knowledge. A number of scientists who have in dividually contributed to the growth of the subject gave invited papers at the Fourteenth Symposium of the Society for the Study of Inborn Errors of Metabolism in the University of Edinburgh on 13-16th July, 1976. These papers form the basis of this monograph which brings together contributions from the basic sciences and from physicians concerned primarily with human disease. The cross-fertilization produced by this interdisciplinary communica tion was invaluable to those trying to understand and overcome diagnostic problems posed by hereditary metabolic disease. Cell culture methods and cell preservation techniques were described by D. G. Harnden and D. E. Pegg; Dr T. Elsdale outlined some of the factors which control in vitro cell growth and division. Cell culture methods and cryopreser vation techniques have allowed the wide distribution of biochemically abnor mal cells and their study over long periods of time. It is also evident that when a defect which produces severe metabolic disorder in man can be studied in the laboratory using isolated cell cultures a wide variety of investigative procedures can be focused on to the cellular defect without distress or discomfort to the patient or relatives."

The rapid growth of immunology has greatly increased our understanding of disease; this growth has also generated a subject which at times appears separated from some of the basic medical sciences. Recent studies in the areas of purine metabolism and of polymorphonuclear neutrophil phago cyte function have, however, linked immunology and clinical medicine with biochemistry. The precise defects of the inborn errors of metabolism have now provided good evidence for the importance of purine metabolism specifically the enzymes adenosine deaminase and nucleoside phosphorylase in lymphocyte function. In view of this and the steady advance of clinical and biochemical investigation of the polymorphonuclear neutrophil phago cyte, it appeared timely to review the inborn errors of immunity and phagocytosis at the fifteenth annual symposium of the Society for the Study of Inborn Errors of Metabolism at Elsinore, Denmark on September II-14th, I 77. The papers presented at that meeting form the basis of this volume which brings together contributions from immunologists, biochemists and clinicians. This interdisciplinary communication should be helpful to those concerned with immune function in their patients or in the laboratory. The book is divided into four sections, One: defects of cell-mediated immunity, Two: enzyme defects and immunodeficiency, Three: disorders of non-specific immunity and Four: screening for immunodeficiency. Section One contains two reviews, one on immunodeficiency from Robert Good's group in New York and another on the genetics of the immune system from Arne Svejgaard of Copenhagen."

The first symposium of the Society for the Study ofInborn valuable overview of advances in the application of Errors of Metabolism (SSIEM) on the organic acid urias chemical analysis of amniotic fluid to their early prenatal was held in Leeds in 1971 and published by the Society in diagnosis. The continuing complexity of diagnosis, 1972 (the 9th Annual SSIEM Symposium). Although biochemistry and aetiology ofthe dicarboxylic acid urias relatively few of these disorders were recognized at that has been admirably reduced by the papers from Dr time, the symposium was prompted by the then recent Gregersen and Dr Goodman, with Dr Goodman clearly identification between 1966 and 1970 of isovaleric identifying the primary defect in the polycystic variant of acidaemia, methylmalonic aciduria, propionic aci- multiple acyl CoA dehydrogenase deficiency ("glutaric daemia, pyroglutamic aciduria and 3-methylcrotonyl- aciduria type II") as a deficiency of electron transfer glycinuria. Identification and diagnosis of diseases of this flavoprotein (ETF) dehydrogenase. Dr Engel's paper kind had greatly improved primarily through the also provides a useful overview from currently available application of gas chromatography and mass spectro- data of the place of L-carnitine in the organic acid urias, metry to medicine, although the complexity of the an area in which rapid developments are occurring. The underlying biochemistry and the genetic heterogeneity of emerging understanding of the aetiologies of the the organic acidurias was not then realised.