Temperamnet in boas is maybe 25% genetics and 75% how it's treated.
I'm not saying you are a bad keeper if you have a defensive boa. I'm saying that you haven't done everything you can to observe it and learn what it needs. Temperatures, caging, lights, the way it is fed and handled.. the whole deal.
Tame boas aren't tame because of some TAME gene, they seem tame because they are more adapted (by accident) to average conditions in captivity. Possibly, seemingly tame boas may produce more seemingly tame babies but that is because of the package of traits they have from many thousands of generations and is likely not much enhanced by 2 or 10 generations in captivity.
In my opinion...
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Gus
A. Rentfro
RioBravoReptiles.com
"Quality is not an accident. Perfectly healthy animals are a minimum requirement.. everything else is just salesmanship" gus