"A subject collection from Cold Spring Harbor perspectives in biology."

Developmental biology has been transformed recently by discoveries in the fields of molecular biology, cell biology, and immunology. New ways of manip ulating mammalian development are uncovering control mechanisms and ena bling us to apply them in solving practical problems in animal production and human health. This book outlines some of these new manipulations and how they have contributed to the present state of developmental biology. Chapter 1 describes gene transfer by micro injection of cloned recombinant DNA into zygotes. Although the factors that affect transformation frequencies and integration sites are still unknown, such techniques offer a number of exciting prospects. Research models for human disease coula be artificially created and desirable characteristics in agricultural animals could be - hanced. . The theme of cell-to-cell transfer is continued in Chapters 2 and 3. Chapter 2 describes pronuclear transplantation by Sendai virus-induced fusion of the karyoplast with the enucleated embryo. Using this procedure, it has been dem onstrated that both male and female genomes are essential for normal develop ment, although the reason for this is not yet understood. Chapter 3 describes studies on the fusion of whole oocytes. .

Assists policymakers in evaluating the appropriate scientific methods for detecting unintended changes in food and assessing the potential for adverse health effects from genetically modified products. In this book, the committee recommended that greater scrutiny should be given to foods containing new compounds or unusual amounts of naturally occurring substances, regardless of the method used to create them. The book offers a framework to guide federal agencies in selecting the route of safety assessment. It identifies and recommends several pre- and post-market approaches to guide the assessment of unintended compositional changes that could result from genetically modified foods and research avenues to fill the knowledge gaps.

Yury Verlinskyand Anver Kuliev Reproductive Genetics Institute, Illinois Masonic Medical Center, 836 W. Wellington chicago, IL 60657 Although introduction of a first trimester prenatal diagnosis by chorionic viIIus sampling (CVS) has considerably improved the possibility for prevention of genetic diseases, it requires a selective abortion in case of an affected fetus. Following the direction of an earlier prenatal diagnosis and to avoid the need for abortion, preimplantation genetic diagnosis has been initiated based on polar body removal and pre-embryo biopsy. The First International symposium on Preimplantation Genetics, Chicago, September 17-19, 1990, was organized to explore these important developments, to review the state of knowledge in the field, and to address existing problems to be solved for developing and improving current approaches for preimplantation diagnosis of genetic disorders. A growing interest in the subject was obvious from the wide attendance of the meeting: over 250 scientists from 19 countries participated. This was the first attempt to put together the advances in different areas of basic and applied research relevant to Preimplantation Genetic Diagnosis, with the multidisciplinary scientific program including the sessions on embryology, micromanipulation and biopsy, genetic analysis of gametes and pre-embryos, IVF, gene expression and gene therapy, and ethical and legal issues. The deliberations of the Symposium presented in the above mentioned sessions, which comprise the contents of correspond ing sections of the Proceedings, open a newarea in medical research based on the interaction of IVF and New Genetics.

Scientific Frontiers in Developmental Toxicology and Risk Assessment reviews advances made during the last 10-15 years in fields such as developmental biology, molecular biology, and genetics. It describes a novel approach for how these advances might be used in combination with existing methodologies to further the understanding of mechanisms of developmental toxicity, to improve the assessment of chemicals for their ability to cause developmental toxicity, and to improve risk assessment for developmental defects. For example, based on the recent advances, even the smallest, simplest laboratory animals such as the fruit fly, roundworm, and zebrafish might be able to serve as developmental toxicological models for human biological systems. Use of such organisms might allow for rapid and inexpensive testing of large numbers of chemicals for their potential to cause developmental toxicity; presently, there are little or no developmental toxicity data available for the majority of natural and manufactured chemicals in use. This new approach to developmental toxicology and risk assessment will require simultaneous research on several fronts by experts from multiple scientific disciplines, including developmental toxicologists, developmental biologists, geneticists, epidemiologists, and biostatisticians.

Experimental Manipulation of Gene Expression discusses a wide range of host systems in which to clone and express a gene of interest. The aims are for readers to quickly learn the versatility of the systems and obtain an overview of the technology involved in the manipulation of gene expression. Furthermore, it is hoped that the reader will learn enough from the various approaches to be able to develop systems and to arrange for a gene of particular interest to express in a particular system. The book opens with a chapter on the design and construction of a plasmid vector system used to achieve high-level expression of a particular phage regulatory protein normally found in minute amounts in a phage-infected bacterial cell. This is followed by separate chapters on topics such as high-level expression vectors that utilize efficient Escherichia coli lipoprotein promoter as well as various other portions of the lipoprotein gene Ipp; DNA cloning systems for streptomycetes; and the design and application of vectors for high-level, inducible synthesis of the product of a cloned gene in yeast.