James Watson had discovered the double helix structure of DNA by his mid-20s. Discovering a woman who would love him was a good deal harder. “Naturally I wanted a girlfriend,” he told a large crowd gathered to hear him at a talk sponsored by the University Bookstore at the Biological Sciences Learning Center Tuesday night. The talk was a homecoming for Watson, who spent his undergraduate years at the University of Chicago.

Watson’s search for love, the way DNA’s molecular instructions are translated into the protein building blocks of the cell, and the physicist George Gamow, who influenced his ideas on genetics, form the subject matter of his new book, Genes, Girls, and Gamow. The tour for the book brought Watson to the University to reminisce about his days as — along with Francis Crick — the most famous biologist in the world and a single guy on the prowl.

Watson and Crick discovered the structure of DNA at Cambridge in the mid-1950s, a discovery that revolutionized biology and gave rise to the modern science of genetics. Watson recalled that he was briefly elated by the discovery, but soon grew ready for new challenges. “I gave, I think, five talks, and I was bored with it. It was pretty simple,” he said.

The next professional challenge, he decided, would be to understand how genes built the body. As part of his research, Watson ended up as a biochemist at Harvard, where he was able to pursue his next personal challenge: finding a girlfriend. He chose Harvard for a reason. “I was very keen to get a job at Harvard because there were women,” Watson said. “There were very few women at Cambridge and then I went to Cal-Tech, which was even worse. Don’t go to Cal-Tech if you want a girl.”

There was one girl he immediately fell for: Christa Mayr, daughter of the renowned evolutionary biologist Ernst Mayr. Christa Mayr was not interested in Watson, but she did save his letters and gave them back to him for the new book. Watson was startled to find a record of his old ideas on DNA translation interspersed among the letters. “I had forgotten all my bad ideas but I remembered bad dates,” he said.

According to Watson, there were many bad dates to come and fewer bad ideas. He recalled watching his group of scientific friends muddle through their social lives. “Gamow’s marriage fell apart. Feynman’s marriage fell apart. We weren’t necessarily socially adept,” Watson said.”People think we guys are different and we aren’t. We make the same mistakes: don’t know how to tell a girl you don’t like her or how to tell a girl you like her.”

But then, Watson admitted that he had his own difficulties. “I was pretty self-centered. Any girl who turned the other way was probably doing the right thing,” he said, attributing some of his unpleasantness to his efforts to work out how genes worked. “I think it’s partly your own preoccupation with what you’re trying to do.”

Watson has been accused in the past of stealing credit from Rosalind Franklin, the brilliant researcher who came very close to discovering the double helix before she died of ovarian cancer resulting from the X-rays she used to determine DNA’s structure. “I haven’t apologized for mistreating Rosalind Franklin, which I never felt I did, so why apologize?” Watson said.

“Deep down, you see, she was a nice person, but the way she reacted to people, I’d say she was more unpleasant than I was. Probably never kissed once in her life, very sad. There were several men who might have wanted to kiss her.”

Watson also dismissed the comments of Barbara Ehrenreich, the biochemist who reviewed his book in the New York Times Book Review. Ehrenreich gave the book a mediocre review, calling Watson’s attitude toward women antiquated and his science overly reductionist and reliant on the genome to explain cell function.

“A rather uninformed, bitter feminist. If she dislikes the genome project, you know she’s a fool,” Watson said.

Watson had kinder words for the University of Chicago, where he majored in zoology. “I don’t think I could’ve got a better education than I got at Chicago,” he said. “I finally understood Chicago. It was officer’s training school. You were knocked down for bad thinking.”

Here, too, though, he had girl problems. “I was not exactly a social success here at the University of Chicago. The only consolation was that most of the student body was not a social success,” Watson said.