AJ McLean: Good Genes or Good Docs?

AJ McLean needs to quit playing games with our hearts.

Here’s a 19-year-old version of the goatee sportin’ boybander in Miami Beach back in 1997 (left) and 18 years later ... the fully bearded 38-year-old at a charity event in Los Angeles in 2015 (right).

"Larger than life."

The question is...