Peter Zhelev, 2000. Genetics and Breeding 30 (3-4) 65-66.

During many years among the most important books on quantitative genetics that helped the breeders, were the books of two British centres of quantitative genetics, in Birmingham and in Edinburgh. These were ``Biometrical genetics`` by Mather (1949), Mather and Jinks (1982), followed after the death of both authors by the successor book ``Genetical analysis of quantitative traits`` written by Kearsey and Pooni (1996), from the Birmingham school, and Douglas Falconer`s ``Introduction to Quantitative Genetics`` (four editions since 1960 to 1996). A more sophisticated book is ``The mathematical theory of quantitative genetics`` (Bulmer, 1980).

All these book have been useful. Birmingham school dealt with almost pure inbred plant lines, with only two alleles at each segregating locus, while the Edinburgh school on animal genetics and evolution allowed for higher heterozygosity and number of alleles. Therefore, the two schools had little to say to each other, but the books of both Falconer and Mather (and his students) were of particular use for the geneticists and breeders in the respective fields. All these books (and some others) served, and still serve as very important handbooks to anyone dealing with quantitative genetics and applying its principles to practical breeding.

During the recent years, however, a lot of new methods and approaches have been developed, in addition to the conventional quantitative genetic methods. They include development of the methods of Quantiative Trait Loci (QTLs) and genome mapping, and many other methods, incorporating the new findings of molecular biology. Indeed, in the fourth edition of the Falconer`s book, written together with Trudy FC Mackay (1996), a chapter on the QTLs was included, but the need of a new comprehensive issue, combining the molecular and classical genetic methods was more and more visible.

The book of Michael Lynch and Bruce Walsh comes to fill in this gap. It is the first volume published of a two-volume handbook entitled ``Fundamentals of Quantitative Genetics``.

The book is organized in 27 chapters belonging to four main parts. Number of topics is astonishing. The authors cover many areas of molecular, quantitative and evolutionary genetics. The first part (chapters 1 to 11) deals with the genetic basis of quantitative traits. The basic concepts and terms in quantitative genetics are presented here in a very comprehensive way. Readers may learn about the main statistical concepts, such as properties of distributions, covariance, regression and correlation, decomposition of genetic variation to its components etc. These topics are not new, since they present in the other more specialized statistical textbooks, but they are very necessary introductory notes.

The second part (chapters 12 to 16) includes five chapters and all they describe the relatively new topic of quantitative trait loci (QTLs), and the different method for their detection and mapping. The authors describe thoroughly and in details the quantitative variation underlying QTLs. This is a very important part, since combining the quantitative and molecular genetics and genome mapping becomes more and more advantageous in many areas, ranging from human medical genetics to plant breeding. The broad scope of this chapter is evident by the fact, that authors provide theoretical basis of mapping of wide variety of organisms, ranging from inbred homozygous lines, that is of interest for breeding of crop plants, and outcrossed pedigrees, interesting for outcrossed plants, animal and medical genetics.

The third part (chapters 17 to 27) presents a vast diversity of methods for estimation the parameters of quantitative variation. Again all the fields of genetics and breeding are covered, and the methods and estimation procedures provided range from parent-offspring regressions and sib-analysis to Best Linear Unbiased Prediction (BLUP) method for estimating breeding values and REML method for estimation of variance components. But they include also very useful and practical topics, such as Genotype x Environment interactions, genetic correlations among different traits, sex-linked phenomena etc. The descriptions of ANOVA techniques for estimating such important parameters like heritabilities, variance components and different effects, causing quantitative variation, could be highly appreciated.

The last part consists of appendices, providing information on the statistical background, underlying several advanced methods.

The book is providing in fact the whole theory of quantitative genetics, including the newest scientific topics and achievements. Authors use abundant biological examples to illustrate the theory and this help the readers without a sophisticated mathematical training to understand the topics.

A topic that I searched for, and that is of particular interest for the breeders and evolutionary geneticists, is the population response to selection. Evidently, it will appear in the second part of the volume, which I will expect impatiently.

The theory presented could have enormous areas of application. Many readers relate the term ``quantitative genetics`` to the breeding. Lynch and Walsh show that it is well related to the population and evolutionary genetics, and may be of use even for such areas, as conservation genetics. In another book the first author (Lynch, 1996) pointed out that quantitative genetic perspective in conservation biology is still neglected, but it is promising, since the quantitative traits are more related to fitness and respectively to conservation practice, than are many neutral biochemical markers.

The volume is written in a very comprehensive and readable way. Of course, not all the chapters will be of use for a particular geneticist or breeder. But everyone could find his own topics of interest. And at the price of the book, it is a real gift to scientific community. Even though, the book may not be accessible to everyone interested. To these I could recommend to visit the webpage: http://nitro.biosci.arizona.edu/zbook/book.html where the essentials of the volume are presented, together with some identified (but only minor) errors.

Lynch and Walsh wrote that the book would be easy to read even for those with limited and basic mathematical training. I could argue (based on my own experience) that some chapters require more profound theoretical and mathematical background than a basic one. But I believe that anyone will surely find many topics of interest and will use the volume as a very important handbook and reference. My final remark is ``Admirable book``!

REFERENCES

Bulmer, M.G., 1980. The mathematical theory of quantitative genetics. Clarendon Press, Oxford, 255 pp.

Falconer D.S., 1960. Introduction to Quantitative Genetics. Oliver & Boyd, London.

Falconer D.S., 1981. Introduction to Quantitative Genetics, Second edition, Longmann, London.

Falconer D.S., 1989. Introduction to Quantitative Genetics, Third edition, Longmann, London.

Falconer D.S., Mackay T.F.C., 1996. Introduction to Quantitative Genetics. Fourth edition, Longmann & Co, London.

Kearsey M., Pooni HS., 1996. The Genetical Analysis of Quantitative traits. Chapman & Hall, London.

Lynch M., 1996. In: Conservation Genetics. Case histories from Nature. (Ed. by J. Avise and J. L. Hamrick). Chapman & Hall, London.

Mather K., 1949. Biometrical genetics, London.

Mather K., Jinks JL., 1982. Biometrical Genetics, 3d ed., Chapman and Hall, London.


Peter Zhelev
University of Forestry
1756 Sofia, Bulgaria
e-mail:zhelev@ltu.acad.bg