G6PD deficiency

The medical screening process is the one where most applicants have problems. On the various PC online communities, without a doubt the #1 type of question from applicants is medical in nature.

"Do they have tampons in Bolivia?"
"What if I was clinically depressed for three years?"
"Will the PC office care if I am fairly obese?"
"I got asthma."

I didn't think I would have a single problem with medical screening. I am a fit young man, with no history of mental problems nor any medications I have to take regularly. So it was a surprise when lab reports came back saying that I was deficient in G6PD. It might've been a lab mistake, I thought, because sometimes the blood is sensitive to being left out past a few days and not being tested. So I got retested and that confirmed that there was no mistake.

G6PD is glucose-6-phosphate-dehydrogenase, which is an enzyme. It converts glucose-6-phosphate into 6-phosphoglucono-δ-lactone and is the rate-limiting enzyme of the pentose phosphate pathway. I had to learn about this shit in microbiology and I hated it.

Basically, if you are deficient in G6PD, then you can't eat fava beans (which is why it is known as favism) and can't take the antimalarial primaquine. If you do [eat fava beans or take primaquine], you can go into hemolytic shock and maybe die. It is said to be the most common and thus most studied enzyme deficiency in the world, and it confers some type of resistance to malaria. More info here if you care.

This condition disqualified me from serving in any malarial countries. No Latin or Central America, no Southeastern Asia, and definitely no Africa.