A dictionary of genetics

from: Piozzi, H. L. [Thrale]. Anecdotes of the late Samuel Johnson, LL.D., during the last twenty years of his life. Reprinted in: Hill, G. B., ed. Johnsonian miscellanies. Oxford: Clarendon Press; 1897, and found by this reviewer on the web at samueljohnson.com. We look to dictionaries for a variety of purposes: pronunciation, definitions, and etymology. In addition, my wife's deteriorating Webster's 7 th New Collegiate is one of my favorites because of its biographical names, pronouncing gazetteer, list of rhymes, and its somewhat outdated list of American Colleges and Universities. One of the great pleasures I associate with dictionaries is how they remind me of my old college friend Steve Blasberg, a human dictionary who would always respond to an unusual word with "not to be confused wi th . . . " followed by an even more obscure semi-homonym and its definition. Although the mix of utility and pleasure is undoubtedly different for different users, there is clearly a market for dictionaries of all kinds. Searching Amazon.corn for "dictionary" returns 16,547 entries (today), including the recent fifth edition of King and Stansfield's A Dictionary of Genetics. A Dictionary of Genetics reminds me of our treasured Webster's 7th New Collegiate in that it also contains some gems in the appendices: a table of taxonomic classification, a list of domesticated species and their scientific names, a list of journals, journal publishers, and even the translations of foreign words found in journal names (e.g., if you did not already know what Comptes Rendus meant, you now know where to look it up). Appendix C contains a chronology of important discoveries related to genetics from the invention of the first compound microscope in 1560 to the demonstration of translational control by a homeobox protein in 1996. Even better, King and Stansfield provide an author index to their chronology. The bulk of A Dictionary of Genetics is the definition of terms. Pages 3-370 out of the total of 439 cover definitions from A (four meanings: mass number for an atom, a haploid set of autosomes, ampere, and adenine or adenosine) to zymogen granules (enzymecontaining particles elaborated by the ceils of the pancreas; not to be confused with zygonema, which, despite being an anagram of "a zymogen," is a stage of meiotic prophase I). More than 6500 definitions occur in the intervening entries. This is a pretty impressive collection of entries for a modestly priced and reasonably sized book. Any dictionary is a compromise between coverage and size. King and Stansfield have tried to include not only terms from hardcore genetics, but also from closely related fields, such as chemistry, biochemistry and paleontology. It is clearly impractical to include a comprehensive list of definitions based on gene names from model organisms, but a few of the more famous genes get their own entries. While one can quibble with the omissions (e.g., why Notch but not White?) the included markers are generally of historical importance as parts of paradigm systems or are involved in diseases. The second obvious criterion for evaluating a dictionary is accuracy and clarity in the definitions. I was delighted to see King and Stansfield's editorial comment in their definition of homology: