Chemistry Nobel Honors 2015

Have you heard about the 2015 Nobel prizes in Chemistry?

For their work on the mechanisms of DNA repair three scientists were awarded, namely: Paul Modrich, from the Howard Hughes Medical Institute and Duke University School of Medicine; Aziz Sancar, from the University of North Carolina; and Tomas Lindahl, from the Francis Crick Institute and the Clare Hall Laboratory won for their studies about DNA's repair mechanisms.

The DNA molecule can be altered or damaged by radiation, sunlight, toxic man-made or natural chemicals compounds. In fact, normal reactions inside the cell produce reactive oxygen species capable to damage the DNA. Moreover, when the cell is copying its DNA, errors happen at a constant rate. If these errors are not removed, they become fixed and can cause diseases. In order to cope with all these sources of DNA damage, cells have evolved complex defence mechanisms, including to repair DNA lesions.

Thomas Lindahl discovered the base excision repair (BER) mechanism in 1970, that occurs when a base of a nucleotide is damaged and this mechanism doesn't allow a mutation is determined in our DNA. .

Paul Modrich discovered the cellular mismatch repair mechanism in cells. When DNA is copied during cell division, mismatch nucleotides can be incorporated into the new strand and it is problematic. So, the cellular mismatch repair mechanism detects and eliminates errors, allowing you to make a correct copy of DNA and helps avoid complicated mutations.

And Aziz Sancar contributed discovering the nucleotide excision repair (NER) mechanism that removes DNA damage induced by ultraviolet light. When the error is  acknowledged the entire nucleotide is removed, not just the base.