what do you mean by "~1 SNP?" one de novo amino acid substitution? or inherited? we have millions of variants.

the redundancy of codons - several codons code for most amino acids, and one-base-pair changes are often synonymous or will code for similarly-charged residues - provides some protection.

on the other hand, if you have a mutation in, say, a non-coding intronic splice site, that can really fuck a protein up. I got unlucky there.

Not true at all.

So much charming and well intentioned misinformation on this thread; as much as if I were to weigh in on the pros and cons of MariaBD versus PostgreSL.

Coding sequence is under significantly higher levels of active “purifying” selection than regulatory DNA, and much higher than de novo mutations in repetitive mobile elements that only rare perturb phenotypes.

Single point mutations in regulatory elements such as enhancers have been shown to change the expression levels of multiple genes. These elements are under just as much selective pressure as any coding region.

not all noncoding dna is going to be a regulatory element.