Rich made major contributions to understanding the relationships between the structure and function of RNA and DNA, and in doing so mentored generations of students. He led a team of MIT researchers to discover a “left-handed” form of DNA called Z-DNA — and revealed that single-stranded nucleic acid molecules could combine to form double and triple helices. He also found that an RNA strand and a DNA strand could come together to form a double helix, helping to explain how cells transcribe DNA into mRNA.

Photo credit: Donna Coveney