Inheritance of Magical Abilities

[mdconnolly at hotmail.com]

No: HPFGUIDX 25510

Apologies if this question has been asked before, and if it has could 
somebody please point me in the direction of the original message.

Hermione's parents are both Muggles, whereas she is a witch. So how 
come she was born with magical powers? Is it a recessive gene? Also 
if witches can be born to Muggles, then can Muggles be born to 
witches?

Thanks,
Martin.