Molecular and developmental biologist Maria Jasin studies DNA repair and how the process is affected in certain cancers, and was recently announced as a recipient of the Shaw Prize for life science and medicine.
Shaw studies how cells fix a form of DNA damage called a double-strand break (DSB), where both strands of DNA are broken, through a process called homologous recombination (HR). In HR, cells repair breaks in DNA by using the cell’s other copy of DNA as a template. It was known that HR could occur in bacteria and yeast, but Jasin was the first to show that this process occurs in mammals as well. And she went on to study the proteins and processes involved.
You might have heard of BRCA1 & BRCA2 genes in the context of mutations in them being associated with breast cancer. Jasin found that the proteins they make are crucial for successful HR, and she worked out some of their roles, finding that both are critical for successful HR, but they act at different steps in the process. And she’s studying the roles mutations in these, and other HR proteins, play in different cancers and developmental contexts.
Jasin’s work has also contributed to gene editing technology, but she didn’t set out to study gene editing. She was (and still is) interested in how cells naturally repair damaged DNA and how those repair processes are disrupted in some types of cancer. But these natural processes can be harnessed to edit DNA by causing precise DSBs and providing an alternate template to use for the recombination step.
CRISPR/Cas is a gene editing technique that involves making breaks in DNA at dictated locations that the cell has to fix. One way to fix the break is non-homologous end joining (NHEJ) which is highly error-prone and often makes changes that functionally inactivate or “knock out” the gene, which is useful for studying what genes do what. Alternatively, you can provide an alternative piece of DNA that matches it, that DNA can get inserted through HR, the process Janis has elucidated, helping pave the way for targeted gene editing.
Jasin is a member of the Developmental Biology Program at New York’s Memorial Sloan Kettering Cancer Center and a professor at Cornell University’s Weill Graduate School of Medical Sciences. She obtained a Ph.D. from the Massachusetts Institute of Technology (MIT), then performed postdoctoral research at the University of Zürich and Stanford University.
Her most recent award, the Shaw Prize, is given by Hong Kong’s Shaw Prize Foundation. Her other honors include election to the National Academies of Sciences and Medicine and the American Academy of Arts and Sciences. Photo Credit: MKCC