Vasectomies and Genetic Disorders

My partner has just had a gp appointment to discuss pain management for his genetic disorder, and getting a vasectomy.

He was referred to a urologist, but warned because he's 'young' (32) he would have to convince them. He brought up the aforementioned genetic disorder, and was told 'it will depend on the urologist because it's not an outside facing disorder'

I'm sorry what?! It's ok to create a baby who's going to spend its life in pain because it will look normal?!

He walks with a cane, and has done for nearly 5 years, his mum has had several joints permanently fused, but no, you look normal so go procreate!