Highly conserved non-coding non-essential DNA
From EvoWiki
DNA aquires mutations over time at a steady rate (the molecular clock), which creates variation between the DNA of individuals. DNA regions that are vital for survival, such as those that code for enzymes, aquire less mutations over time than non-vital regions because selection acts to homologise these vital areas.
In 2003/04 a team led by Edward Rubin investigated regions of such conserved DNA in the genomes on mice. These regions were non-coding, but were more conserved than many genes, so it was assumed that they must be vital for the survival of the mouse. However, when the team removed the area there was no observable change to the mice, leading to a number of so far unanswered questions:
- Are these areas Junk DNA, if so why are they so highly conserved?
- Was the role of the DNA region taken over by similar regions elsewhere?
- What molecular or cellular mechanism would require such conservation?
Source
- Westphal, S.P., 2004. Life still goes on without 'vital' DNA, NewScientist No. 2450, P.18.
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This page is part of the EvoWiki encyclopedia of genetics and molecular biology. Topics: Genetics - Transmission genetics - Molecular genetics - Population genetics - Quantitative genetics - Molecular biology - Genomics |
