I thought you may find this interesting. I couldn't find info about what was his starting vertical jump, but now it is reportedly 44".
Would that make him genetically gifted for jumping from the get go (and then he did all the hard strength work to make the leap to the basketball rim for a 5'5" guy?)
In any case, I think it adds ammo to the argument that strength training should give you explosive jumping power even when adding on substantial weight (85lbs in his case).
Excerpted from the Atlantic:
At 5’5”, Brandon Todd had a seemingly impossible goal: to be able to dunk a basketball...
Inspired by Russian powerlifters, Todd trained himself to dunk the ball through rigorous strength training, as well as running and jumping exercises. Over three years, Todd gained 85 pounds of muscle before he was finally able to dunk the ball. “I was willing to put myself through all this pain and anguish for that one moment to say: ‘I can do it.’”
For those interested Google searching his name pulls up all the relevant wiki, videos etc...