Before questioning Dark DNA existence, one should understand what is Dark DNA?
We call the hidden sequence “dark DNA” as a reference to dark matter, the stuff that we think makes up about 25% of the universe but that we can’t actually detect.
So the dark DNA is sequence which is present in genome;
- but they are misplaced (that’s what we say),
- are all rich in G and C molecules, which have historically been difficult for gene-sequencing technology to detect,
- they aren’t turning up where we expect them, they’ve managed to slip our attention,
- this makes it more likely that the genes we were looking for were hard to detect rather than missing.
Ref:Genome sequence of a diabetes-prone rodent reveals a mutation hotspot around the ParaHox gene cluster
In one study these are called as mutation HOTSPOT, in other these are just missing DNA seq. But surprisingly the genes called as dark DNA are found in similar animals/organisms and essential for survival, so how can they disappear from other organism.
Yes they are essential because even when they are missing, their products have been detected (above link).
Genome and evolution are still a big mystery, so much is left to find out and connect the missing dots of evolution.