I guess time will tell if it leads to any adverse effects. I'm not a biologist which is probably why I'm more wary of this, but if there is some unforeseen circumstances then we'll find out I suppose.
The trouble here is that we can't see those consequences until they end up hurting someone.
Imagine trying with million or tens of million year code.
- it's been written for billions of years (https://en.wikipedia.org/wiki/Abiogenesis#Earliest_biologica...)
- without any sort of upfront architecture or planning
- the development methodology can be summarized as "change characters randomly and see if it compiles"
- incredibly bloated (https://en.wikipedia.org/wiki/Non-coding_DNA)
- contains random snippets copy/pasted from other codebases (https://en.wikipedia.org/wiki/Endogenous_viral_element)
- the only success criteria is that the "program" shouldn't "crash" before it can make a copy of itself
>The vertebrate retina is inverted in the sense that the light sensing cells are in back of the retina, so that light has to pass through layers of neurons and capillaries before it reaches the rods and cones. In contrast, in the cephalopod retina the photoreceptors are in front, with processing neurons and capillaries behind them. Because of this, cephalopods do not have a blind spot.
This would actually be preferable to how DNA seems to evolve. In most systems, there's actually quite an acute constraint to genome length due to the Error Threshold; when a genome gets too large, it has too many mutations and therefore the 'fittest' genome, often called the 'master' genome, cannot be sustained in the population. Therefore, there's quite a lot of evolution where the genome becomes essentially minified. Most often, this is done by overlapping genes on the DNA, (mostly by shifting the reading frame by one or two nucleotides for one of the two genes).
edit: I'll also amend the statement, as the gene is implicated in responses to other viruses: https://en.wikipedia.org/wiki/CCR5#Potential_costs
Take height: Height is extremely heritable. If your parents are both tall, you are very likely to be tall as well. But height is influenced by thousands of genes, and each individual gene has only a minuscule influence. And each of those genes is also responsible for many other unknown things.
It's not at all a reasonable assumption that genetic modification will allow us to influence a complex trait like intelligence. That's just wishful thinking.
But that's very different from designing an embryo by direct genetic modification.