What is the disease that causes passing out?

Vasovagal syncope (vay-zoh-VAY-gul SING-kuh-pee) occurs when you faint because your body overreacts to certain triggers, such as the sight of blood or extreme emotional distress. It may also be called neurocardiogenic syncope. The vasovagal syncope trigger causes your heart rate and blood pressure to drop suddenly

Explanation:

Hope this helped

-A Helping Friend

answer; genes dictate the production of specific enzymes, and affected individuals have genetic defects that cause them to lack certain enzymes;

i'm pretty sure questions like these aren't allowd.   but, sure.   i can and talk : ))