Alpha-1 antitrypsin deficiency (pronounced "alfa-one anti-trip-sin") is a genetic condition than can cause lung and liver disease. Often called Alpha-1, this condition is caused by low levels of a protein in the blood called alpha-1 antitrypsin (AAT).

Normally, the AAT protein is made in the liver and then released into the blood stream. AAT is most important in the lungs and the liver where it protects against enzymes that break down cells. When AAT is low or missing, the elastic tissue in these organs becomes damaged and can't function properly.

Because people with Alpha-1 have low or no AAT, they can develop lung, liver, and other complications. These can range from severe to mild to no symptoms at all. How serious the effects are depends on many factors.

Not all people who inherit Alpha-1 develop complications. However, all people who have inherited Alpha-1 can pass the genetic changes on to their children.

Alpha-1 is easy to diagnose, but many people who have it are never tested for it. This is because the signs and symptoms are common and often mistaken for other conditions. Knowing that Alpha-1 is the underlying cause can help:

• motivate people to make important lifestyle modifications
• healthcare providers offer appropriate treatments
• begin appropriate screening to look for other complications (such as liver disease)
• avoid unnecessary treatments or medical procedures that may not be appropriate for people with Alpha-1