I know that DNA encodes proteins. Truthfully, everything besides that (including ‘what are proteins’) mostly wooshes over my head, but that’s not relevant because whenever I search this question I never even find it addressed anywhere.
The human body has, among other things, two hands each with five fingers, with a very particular bone structure. How are things like that encoded in DNA, and by what mechanisms does that DNA cause these features to be built the way they are? What makes two people have a different nose shape? Nearly everyone in my family has a mole on the left side of their face, how does that come about from DNA?
I’m sure there are many steps involved, but I don’t see how we go from creating proteins to reproducibly building a full organism with all the organs in the right places and the right shapes. Whenever I try to look this up, all of these intermediate steps are missing, so it basically seems like magic.
As I said, any explanation will most likely go over my head and I won’t be able to understand it fully, but I at least want to see an explanation. I’ll do my best to understand it of course.
By the way, in case you’d have a guess for the answer:
If scientists really wanted to, throwing all questions of ethics out the window, would it be possible to genetically engineer a person with four arms instead of two, kinda like Goro? Does our current understanding of this go far enough to make deliberate changes like that? And would that baby be able to develop in a normal woman’s pregnancy?
No, and no. My PhD thesis was on gene delivery. We’re barely getting into the simplest modifications for disease treatment. Multigene stuff, and spatiotemporal control is still a ways off.
I would say sort of. They could do it, but the result wouldn’t survive very long. Probably not even to birth.
I’d guess no, the number of digits and limbs is conserved very well across tetrapods (it’s in their name after all). Fucking with the amount of limbs will probably lead to some developmental errors in the early embryo.