Genome complexity: DNA repair (Introduction)

by David Turell @, Tuesday, February 24, 2015, 15:02 (3321 days ago) @ David Turell

Spell-checking actively protects DNA in cell production, but not completely. Mutations result:-"Ben Lehner and his team had previously described that somatic mutations are much more likely in some parts of the human genome, thus damaging genes that may cause cancer. In a new paper published on 23rd February in Nature, they show that this is because genetic mistakes are better repaired in some parts of the genome than in others. This variation was generated by a particular DNA repair mechanism called "mismatch repair" - a sort of a spellchecker that helps fix the errors in the genome after copying. Lehner and Supek show that the efficiency of this 'DNA spellchecker' varies depending on the region of the genome, with some parts of chromosomes getting more attention than others.-"The work presented by Lehner and Supek sheds new light on a process that was unexplored - what makes some parts of the human genome more vulnerable to damage? "We found that regions with genes switched on had lower mutation rates. This is not because less mistakes are happening in these regions but because the mechanism to repair them is more efficient", explains Ben Lehner, group leader, ICREA and AXA professor of risk prediction in age-related diseases at the EMBL-CRG Systems Biology unit in Barcelona. The 'mismatch repair' cellular machinery is extremely accurate when copying important regions containing genes that are key for cell functioning, but becomes more relaxed when copying less important parts. In other words, there appears to be a limited capacity for DNA repair in our cells, which is directed where it matters most."-http://medicalxpress.com/news/2015-02-dna-spellchecker-genes-equally-mutate.html


Complete thread:

 RSS Feed of thread

powered by my little forum