Mutations Can Cause Problems

Mutations are the raw material of evolution, giving variety that can help an organism thrive in its surroundings. Most, on the other hand, are assumed to be harmless and have no effect on an organism’s fitness. These can be quite valuable since they allow us to follow evolutionary relationships without having to worry about selection for or against the mutation impacting the Mutations frequency. For example, all genetic ancestry tests rely primarily on detecting the existence of neutral mutations.

A study found that a substantial category of Mutations isn’t as neutral as previously supposed. The study was conducted in yeast, which is a strange creature in a couple of respects, so we’ll have to see if the findings hold up in other organisms. The fact that most of our DNA appears to be doing nothing beneficial is one of the reasons why most Mutations are neutral.

Only a small percentage of the human genome is made up of genes that code for proteins, and only part of the adjacent DNA is involved in regulating their function. Outside of such locations, Mutations have little effect, either because the DNA has no function or because the function isn’t sensitive to the base sequence in the DNA.

Each amino acid in a protein is encoded by a three-base combination in DNA. That implies there are 64 alternative codes for amino acids, but we only utilise 20 of them. As a result, the genetic code has a lot of redundancy. The amino acid threonine is encoded by the base series ACG, for example. So does the ACA series. And then there’s ACC. Four distinct codes will bring you threonine in total.