Alexander Rich, who confirmed the double helix structure of DNA, died on April 27 in Boston. He was 90.
While James Watson and Francis Crick are credited for discovering the structure of DNA, it was not until Rich produced a distinct image of the double helix in 1973 that their theory was proven correct. After seeing the image Watson called Rich to thank him, saying that it was the first good night's sleep he'd had in 20 years, The New York Times says in its obituary on Rich.
In addition to validating the DNA double helix structure, he helped figure out the structure of collagen and conducted crucial research into Z-DNA. "While we still do not fully understand its biological role, the work on Z-DNA emphasized perhaps more than any other single piece of data how important the three-dimensional conformation of DNA in the context of the cell is," Thomas Schwartz, an associate professor of biology at the Massachusetts of Institute, said in a statement from the school announcing Rich's death. Schwartz had been a PhD student of Rich's.
NYT added that Rich's research "provided insights into how cells manufacture proteins, and laid the groundwork for techniques that scientists use to identify, manipulate, and replace bits of genetic material." His work has led to technologies that include HIV diagnostics and breast cancer genetic tests, the paper said.
Among the firms that he co-founded are Replenigen and Alkermes.