Shawn Bradley of Dallas ties up Olden Polynice of the Jazz for a jump ball. photo by ravell call, April 24, 2001.

A chance encounter in the first-class section of an airplane led to a giant mystery being answered.

Why is Shawn Bradley so tall?

That’s what BYU biology professor John Kauwe wanted to know after sitting next to the former Cougar basketball player, and the 7-foot-6 ex-NBA center eagerly agreed to participate in an in-depth study to find out.

“Unlike many extremely tall people who have a rare genetic disorder or a pituitary tumor, Bradley is healthy and still one of the tallest people in recorded history,” explained the article ‘BYU genetic researchers solve a giant mystery: How Shawn Bradley got to be so tall.’

“That combination of factors made mapping the genome of the 12-year NBA veteran an enticing scientific endeavor for Kauwe.”

Added Bradley, “I was game — I was very interested to see what he would find out.”

The genetic researcher and his team sorted through 22,539 height-affecting genetic variants that are identified in something called the GIANT Consortium.

Through a complex process, which included sequencing all 3 billion base pairs of Bradley’s genome, the group discovered that he simply had “nearly every common genetic variant that positively affects height.” That put him in the 99.99999th percentile for male height, with the average American man standing 5-foot-10.

In fact, Bradley has 198 more height-associated genetic variants than the average person in a sample of 1,020 participants.

“It appears that if you’re really, really tall, you’ve probably achieved your full genetic potential for height,” Kauwe told “Shawn Bradley definitely realized the full potential of his DNA.”

The full study is included in the International Journal of Genomics.