Do you think humans will be able to genetically engineer future humans in your life time?
do you think humans should be engineering human dna?
are there some events when we should? when we should not?

Yes, they could, but they shouldn't because there can be many mistakes. There are some such as if we want someone to be immune to some diseases. But we shouldn't if it's a situation that we want someone more beautiful!

The bonding properties of carbon
Perhaps more important, however, is carbon's capacity for covalent bonding. Because a C atom can form covalent bonds to as many as four other atoms, it's well suited to form the basic skeleton, or “backbone,” of a macromolecule.
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