Nobel Laureate Tomas Lindahl Speaks on DNA Repair at ZJU


Professor Tomas Lindahl, winner of the Nobel Prize in Chemistry in 2015, delivered a lecture titled “DNA Stability and Repair” at Zhejiang University Global Lecture Series on November 6.

According to the lecture, our DNAs are exposed to ultraviolet radiation and destroyed by free radicals and other cancer-inducing substances every day. Even if they are not subjected to external attack, DNA molecules are far from stable per se. Thousands of cell genomes are undergoing changes spontaneously. In addition, there also exist defects with DNA copying during the process of cell division.

In the early 1970s, scientists thought that DNA molecules were completely stable. During the mid-1970s, through studies of bacteria, Lindahl showed how certain protein molecules, repair enzymes, remove and replace damaged parts of DNA. These discoveries have increased our understanding of how the living cell works, the causes of cancer and aging processes. 

Lindahl has also made a number of significant contributions to understanding at the DNA level the mechanism of transformation of B-lymphocytes by the Epstein-Barr virus. The most notable of these was the first description of the occurrence in lymphoid cells of closed circular duplex viral DNA.

During the Q&A session, Lindahl told students: “Sometimes the answer that ‘We don’t know’ is best for a scientist, because it indicates that we put forward a crucial question, that we know the existence of this particular question, and that we should endeavor to find the answer to this question step by step.”

Asked what was the determining factor for the Nobel Prize, Lindahl stressed the importance of raising a question for which others show their disregard.

When it comes to genetic treatment, Lindahl maintained that DNA transformation should be permitted to diagnose and cure major genetically-induced diseases due to genetic mutation, but it should be employed with the utmost care.

Lindahl received a PhD degree in 1967 and an MD degree qualification in 1970 from the Karolinska Institute in Stockholm. After obtaining his research doctorate, he did postdoctoral research at Princeton University and Rockefeller University. He was awarded the Nobel Prize in Chemistry jointly with American chemist Paul L. Modrich and Turkish chemist Aziz Sancar for mechanistic studies of DNA repair in 2015.