The Nobel Prize for chemistry has recently been awarded to Tomas Lindahl, Paul Modrich and Aziz Sancar for having mapped, at a molecular level, how cells repair damaged DNA and safeguard the genetic information. Over the last decade or so, the Nobel prize for chemistry have all gone to biochemists, and this year’s prize is no exception. Their work has provided fundamental knowledge of how, for instance, a living cell can be used for the development of new cancer treatments.
Every day our DNA is damaged by various forms of radiation, such as UV radiation, by free radicals, and by carcinogenic substances. But even if these external attacks on the DNA did not occur, it would still be very unstable. DNA copies itself whenever a cell divides, and since it is getting copied so often is bound to make mistakes here and there. genetic information decays, and unfortunately the mistakes made by your DNA add up fast enough that humans simply would no longer be here. Evolution itself would break.
It wasn’t until Lindahl, Modrich, and Sancar discovered the Base Excision Repair System and the Nucleotide Excision Repair System that we found out how we haven’t all been wiped out yet. The Base Excision Repair System is an assembly of proteins that slice out erroneous bases out of a stretch of DNA and replace them with the right ones. Nucleotide excision targets more extensive damage that is done by UV radiation. Furthermore, Paul Modrich discovered how cells correct errors that are introduced during DNA copying. When this mismatch repair system malfunctions, it can result in somebody getting colon cancer. All of these are discoveries are essential biochemical knowledge, and they are actually happening within your body right now!