Board Thread:General Discussion/@comment-22027448-20150414115354/@comment-26072045-20150423002720

Mr B Natural wrote: But six-fingeredness (it'll catch on) is a gene that is passed from parent to child. I'm betting that the sixth finger isn't natural.

Or they could just be really, really similar looking fraternal twins. Technically any abnormalities are mutations. My friend has OCD. Why? Because he has a mutation in his genes. However as you said this can also potentially be passed onto his children. For instance people who have no history of little people in their family can still have a genetic anomaly when they conceive a child and have a child with dwarfism.

As for them being identical requiring both to have the polydactyly this is completely untrue. For one thing like I said identical twins can have minor differences. Though their genetic codes are based off of the same thing they aren't exactly identical. This is why identical twins have different fingerprints. It's why Dyland and Cole Sprouse have slightly different builds yet are still considered identical. It's why one identical twin can have major depressive disorder and the other can have no disorder whatsoever.

I've studied genetics a lot so I know it's completely possible for the author's sixth finger to be natural AND for him to still be Stan's identical twin. However it's not necessarily the case. Like you said it could have something to do with magic or whatever.