Alpha-1 Antitrypsin Deficiency
This immortal minute is about the selective advantage of Alpha-1 Antitrypsin Deficiency. Now Alpha-1 Antitrypsin is an enzyme that repairs the lungs and the deficiency for this enzyme is actually pretty common. Approximately 25% of Northern European people carry one of the alleles for this deficiency. Considering that this deficiency is known to be a factor in Chronic Obstructive Pulminary Disorder (COPD), there must be some reason why so many people still carry this defective gene. As it turns out, people with Alpha-1 Antitrypsin Deficiency are initially protected them from upper respiratory infections by their deficiency. But over time, the Alpha-1 Antitrypsin Deficiency damages the lungs causing conditions like COPD.