Principles of genetics

Principles of genetics

Cell, Vol. 23, 635-637, February 1981, Copyright 0 1981 by MIT Book Reviews Picking and Choosing in Genetics Principles of Genetics. By J. W. F...

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Cell, Vol. 23, 635-637,

February

1981,

Copyright

0 1981 by MIT

Book Reviews Picking and Choosing

in Genetics

Principles of Genetics. By J. W. Fristrom and P. T. Spieth. New York and Concord: Chiron Press (1980). $21.95.

687 pp.

For years I have been arguing with colleagues about how genetics should be taught. I have always maintained, in a losing cause, that the historical approach not only allows students to see how the science developed, but also gives proper credit to those who came first. Friends with whom I teach insist that the simplicity of E. coli and its phages makes it easier to convey principles to the students. Genetic mapping is perhaps easier to teach with E. coli or its phages than with Drosophila, where Sturtevant originally worked it out, but sometimes I wonder who is supposed to be simple-procaryotes or students. The numerous new genetics texts-it is hard to understand why there are so many -either choose to segregate Mendelian and bacterial genetics or, increasingly, to integrate the two under grand headings, such as nucleic acids and chromosomes, gene transmission and gene function. Some authors do this better than others. Fristrom and Spieth do it better than most. This book, the product of a long-lived genetics course at Berkeley, is lively and interesting. The authors declare in the preface that they wish to tie evolution and genetics together and then, true to the idea of evolution, they begin with an entertaining account of the Big Bang and the evolution of molecules. One who espouses the historical approach can’t complain. A few pages take us through the standard elementary biochemistry of proteins, RNA and DNA and then to the discovery of nucleic acid as the genetic material. Explained in passing is the tetranucleotide theory of Levene, which slowed acceptance of DNA as the genetic material. The ensuing account of chromosome structure is up-to-date, well illustrated and clear, providing a good basis for later genetic sections, which rely on a knowledge of polytene chromosomes. Before proceeding to transmissional genetics there is an account of eucaryotic DNA complexity, which takes us quickly through density gradients, sequencing, restriction enzymes, hybridization kinetics and some of the results of these techniques. The replication of eucaryotic and procaryotic chromosomes is discussed successfully in the same chapter; here the book follows a more molecular path than most, with descriptions of the enzymology of DNA replication. DNA replication is followed by the transmission of chromosomes, where we finally reach meiosis as well as the rolling circle. The account of meiosis is adequate and, while the obvious importance of meiosis as a reductive division and the disastrous consequences of nondisjunction are mentioned, the

combinatorial assortment of chromosomes is ignored, at least here. The presentation of Mendelian genetics is clear and the uses of probability are well explained. The chapter is limited to the basics, and complex interaction between genes, such as epistasis, are ignored. (The index contains no mention of epistasis, penetrance or gene conversion.) After the account of segregation and independent assortment, the authors tackle the recombination of genes carried on a single chromosome, using X as an example, and then discuss linkage in eucaryotes. The Holliday model of recombination is treated only in terms of phage, while the phenomenon of post-meiotic segregation in fungi which led to the idea is ignored. This tendency to be brief and to ignore details and subtleties recurs throughout the book. It seems that the price of additional molecular biology is the elimination or truncation of many of the subjects and examples one usually finds in older or more classical genetics texts. Depending on your point of view, this may be justifiable-it certainly leaves an instructor using this text plenty of room to expand. This book was not written for an advanced classical genetics course. The problem sets (published separately) are neither extensive nor challenging, tending to be of the compare and contrast variety. In a good genetics course, they would have to be supplemented. Finally, my last quibble is that the authors have tried to inject a sense of humor, with poems and an occasional joke. What passes in the classroom for bonhomie is stilted in a textbook. Someday Woody Allen may write a funny genetics text; until then, the rest of us should play it straight. This is a lively and entertaining text and, while a few subjects are inadequately treated or ignored, this may be the price of getting the bulk of modern genetics between two covers. Richard H. Kessin Cellular and Developmental The Biological Laboratories Harvard University Cambridge, Massachusetts

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The Local Immune Response In Situ Expression of Tumor immunity. Contemporary Topics in Immunobiology, Vol. 10. Edited by I. P. Witz and M. G. Hanna, Jr. New York and London: Plenum Press (1980). 348 pp. $32.50

Tumor immunology has as its practical goals the finding of qualitative (or at least quantitative) differences between the antigen expession of normal and of neo-