Except your premise is based on the precept that if the information changes even slightly, the "information" is then lost, and like changing letters in a book, becomes unreadable.<quoted text>
How do you know that "chemistry is itself the information?". What does that mean? It's the arrangement and sequence of nucleotides that comprises the information.
Now here's reality. We're all born with 125 to 175 mutations which are NOT shared by our parents. And so is each successive generation. There is currently over 7 billion different ways to make a human. Despite this, and the positively ridiculous claims of your Young Earth Creationist buddy Sanford, people who are born with mutations that are a serious detriment to procreation are the exception not the rule. Add to that the population of the human race is increasing, not decreasing as your pathetic apologetics for "TEH FALL" claims.
Now, if we take you as the human "standard" and for the sake of argument say you've got "100% human" DNA profile. Chimps are at 98%, gorillas at 97% and orangutans are 96.
According to you we can have genetic codes which can be 99.9%, 99.8%, 98%, 97%, 96%, but DEFINITELY NOT (no way no how) 99%.
This is absurd.