WHEN HARVARD SCIENTISTS first began to do recogniseand DNA research, in July 1976, the prospect of instant caping from clar catme diabet samed so frightening that. Harvard's bigingincal laborities received a South threat. During that year, Cambridgn Mayor Affecd E. Vellucci, who would laternay. "I have always felt that DNA work should not be done in a city of 100,000 people," worked to address public fears. He sponsored debates on the dangers and benefits of genetic engineering and act up a mock laboratory as his Mayor's Marketplace to inform the Cambridge populace about this new science which promised so much power for good and for evil.

The authors of two new books on genes and DNA (short for deoxyribonucleic acid, the molecule which stores genetic information in the cell) have acted in the educational spirit of Al Vellucci. Both The Gene Age and DNA for Beginners are clearly written expositions which try to demystify molecular genetics for the layman; both, incidentally, include serious discussions of the Cambridge controversy over whether recombinant DNA research should be permitted.

Neither Edward Sylvester and Lynn Klotz, authors of The Gene Age, nor Israel Rosenfield, Edward Ziff, and Borin Van Loon, authors of DNA for Beginners, would necessarily recognize their kin-ship to populist mayor Vellucci. They have adapted to very different environments from Vellucci and from each other: The Gene Age is a clone from the hard-driving, earnest, and competent American biotechnology industry, while DNA for Beginners evolved from the genial and sardonic humor of the English academic New Left.

DNA for Beginners is simply the best introduction to genetics you can buy. Sylvester and Klotz write in The Gene Age that molecular biologists "stand out among scientists as intensely visual, as imaginative rather than analytic." DNA for Beginners puts this visual imagination into pictures. And what pictures they are! Borin Van Loon's clever and exhaustive illustrations should be the required text for anyone who wants to design educational graphics.

A documentary comic book from the prolific Writers' and Readers' Publishing Cooperative. DNA for Beginners succeeds better than similar introductions from the same publisher such as Marz for Beginners or Frend for Beginners, which deal with less visual subjects. Although titled a "comic book," DNA for Beginners should not be confused with science-inspired pulp serials such as "DNA gents" (which details the adventures of a handful of artificial people created by a giant corporation to do its dirty work.) Thoroughly researched, simply written, beautifully laid out, DNA for Beginners is in fact more serious than most popular science writing. With Van Loon's magnificent drawings to grab the reader's attention, the text can remain simple and straightforward and avoid the eye-catching exaggeration all too common in science journalism. Authors Rosenfield precision with an English brevity of expression.

BUT IT IS Van Loon's versatility and imagination as an illustrator which makes DNA for Beginners so entertaining and understandable. The range of his models is extraordinary. He draws on Auguste Rodin's Thinker, Andy Warhol's soup cans, Thomas Nast's cartoons of Victorian social commentary, and dozens of other artists' works. Caricatures, engravings, photographs, and a diagrams are all intermingled without ever clashing. Gregor Mendel's famous pea plants, study of which led to the discovery of genes, show up as Jolly Green Giants.

Even the scientists are portrayed with an astonishing diversity of styles; at different times Van Loon pictures Francis Crick and James Watson, discoverers of the double helix structure of DNA, as Bat. In addition, the comic book format in the only one in which the arcane and often ridiculous jargon of molecular biology makes sense.

WHILE DNA FOR BEGINNERS would make the perfect gift for your favorite dilettante or high school science whix. The Gene Age is best suited for an investor in the fast-paced, high-flying biotechnology industry. Had it come out a couple of years earlier. The Gene Age might have staved off the stock market cruze during which speculators plunged millions of dollars into companies with no products and no foreseeable profits.

Indeed, one of the most useful sections of the books provides guidelines for evaluating biotechnology companies as investments. In addition, Sylvester and Klotz provide an excellent summary of what protein products will soon be made commercially by the genetic engineering industry.

The Gene Age benefits from an insider's understanding of the industry. Lynn Klotz is an executive of Bio Technics International, a genetic engineering firm located in North Cambridge. (Klotz was Assistant Professor of Biochemistry and Molecular Biology at Harvard when recombinant DNA research first began.) His knowledge brings some surprising insights: for example, the commercial production of a drug can often be speeded up if scientists patent the manufacturing process. The sale of penicillin, by contrast, was held back 15 years because its discoverer, Sir Alexander Fleming, had deemed it ignoble to patent the process.

Despite an occasional felicitous phrase--enzymes, for example, are described as "nature's answer to the blast furnace and the 10-ton press"--The Gene Age reads like a scrapbook of competent but unexceptional magazine articles. Sylvester and Klotz write clearly and chattily, but they lack a unifying theme. And their sections on the science of genetic engineering suffer from dull graphics poorly integrated with the text. Even the most sparkling writing could never explain molecular genetics without a good set of pictures; DNA for Beginners is thus far better for anyone interested in genetics out of pure curiosity.

A CURE FOR CANCER is the popular dream of how biological researches benefit from and both books finish with a look at the incredible progress made in the last years by applying genetic tools to studying cancer. The growing understanding of how cancer starts on the genetic level may soon lead to new and more effective treatments. Such speculations bring out what is probably the most frightening thing about these books and about DNA research--the possibility of changing genes to eliminate hereditary disease and, by implication, extend our control almost as far as life and death.

As the world becomes more and more of our own making, it seems less and less under our control. By showing the simple structure which underlies a complex new technology, books such as DNA for Beginners and The Gene Age help us to reassert control over it. DNA for Beginners, in particular, provides a wonderful way to humanize an otherwise bewildering subject.