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Name: Faramarz
Status: Student
Grade:  Other
Location: Outside U.S.
Country: Germany
Date: September 2008

What are the evolutionary differences between coding and non coding DNA? is the mutational force on non coding DNA higher than coding DNA?

First of all, non-coding has traditionally meant DNA that doesn't code for protein. New research shows that this much of this DNA is probably very important in regulating whether genes are on or off, or codes for RNA other than mRNA. Some of it resembles virus DNA and could be remnants of past viral infections in our ancestors that has been passed down over the generations. Some of it resembles other genes but has some mistake in that has inactivated it-we call these pseudogenes. Sometimes genes get duplicated so that there are 2 copies of the same gene.

If one of these mutates and becomes inactive but the other still works it doesn't affect survival. So to answer your question-some of this non-coding DNA is probably very important to the way our DNA works and is selected for. Other DNA is not selected for or against and it hitching a ride through evolutionary time. However, since if mutations happen in this DNA it doesn't affect our survival, these differences accumulate and can be used to determine how closely or distantly related two organisms are evolutionarily. The fewer mutations between two organisms, the more closely related they are through common ancestry. The more differences, the more time has passed since they shared a common ancestor.


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