One of my friends ask me to polish his draft of self-introduction. One of the sentences reads like this:

the reason I choose to explore life science can cast back to my childhood.

The idea he wants to express is that his childhood exerts much influence on why he want to explore life science now.

I feel that his sentence sounds a bit awkward, but I fail to come up with a better sentence.

Who can help me to make a better sentence without changing his sentence patterns too much? Thank you a million!
"The reasons I chose to explore life science began in my childhood" is a possibility - but your friend still has not explained what those reasons actually ARE. Maybe that comes in the next sentence?

It sounds like you said it to me...his childhood exerts much influence on why he wants to explore life science now.
He can say it like "My childhood has influenced my decision (in starting a career in..., in exploring, in developing a liking for) life science.

 rommie's reply was promoted to an answer.