There's almost no difference between one person's vocal cords and another's, except that men generally have larger vocal cords than women.
It's pretty well established that education is important. But learning begins a lot earlier than you might think. "Fetus Learning" on this Moment of Science.
As a boy goes through adolescence, his secondary sex characteristics develop. One of these characteristics is the rapid growth of the larynx and vocal cords. A boy’s voice deepens as his larynx develops because the bigger the vocal cords, the deeper the voice.