Scientists have been unraveling many questions with the help of DNA sequencing technology. Such as how the giraffe got his long neck or what allows cuttlefishes to camouflage it so perfectly?
With the help of genome sequencing, we can compare and contrast several animals DNA and work out on their unique evolution. But researchers got puzzled as they faced a mystery in some cases. The genome of animal had some certain genes missing when those are very important to be alive for other similar species!
So, they named it Dark DNA similar to the dark matter; the matter that scientists think created almost 25% of the universe, yet elusive. It was first noticed by some researchers while they were sequencing the sand rat’s genome. Sand rat is a species of gerbil but lives in deserts. Particularly, they wanted to study the genes of a gerbil that are related to the insulin’s production for understanding why it is especially susceptible to type2 diabetes.
And as they searched Pdxl, a gene controlling the insulin’s section, it wasn’t in the body! It was missing with 87 other genes surrounding it. Some of which are very important and an animal cannot survive without them. So where did they go?
As they started to study it, they began to find clues. The first one is, in many tissues of the body of sand rat they found out that the missing genes would give instruction to create some chemical products. But they were being created without it! This can’t happen, so it means that those genes were somehow present!
Which means they are hidden, not missing. It was also found that especially, one part of it had lost more mutations than the other rodents’ genomes. In this mutation, all the genes are very rich in GC DNA (Guanine-Cytosine DNA), also it has mutated in such a manner that it becomes hard to detect with the standard methods. This type of excessive mutation often leads to stop the working of a gene but somehow, the genes of the sand rats have managed to achieve their roles despite complete changes to the DNA sequence.