As a hereditary condition, Alpha-1 can be passed on from parents to their children through DNA, or genes.2
People with 1 normal gene and 1 defective gene are called “carriers.” Carriers may pass the defective gene on to their children.2
Because Alpha-1 is a hereditary and progressive disease, early testing and diagnosis can help you and possibly your loved ones get appropriate treatment that can help slow the progression of the disease.11
There may be as many as 19 million carriers of Alpha-1 in the United States who are unaware of their condition and have not been diagnosed.2
Because Alpha-1 is hereditary, testing for Alpha-1 is recommended for parents, children, siblings, and extended family of anyone who has been diagnosed with Alpha-1.12
What can your family genes tell you?
Half of your genes are passed on from each parent. You can inherit Alpha-1 from Alphas (people with 2 abnormal A1AT genes) or carriers (people with 1 normal and 1 abnormal A1AT gene).
This figure shows what could happen to children if both parents are carriers. It shows the genes that result in normal A1AT protein levels (M) and low to undetectable A1AT protein levels (Z).
Normal (MM) – Does not have the disorder; does not carry any abnormal A1AT genes
Carrier (MZ) – Mild to moderate A1AT deficiency; may get disease symptoms and does carry an abnormal A1AT gene
Carrier (MS) – It is unclear whether there is a risk for getting disease symptoms but does carry an abnormal A1AT gene (most studies do not show an increased risk for disease)
Alpha-1 (SZ or ZZ) – Moderate (SZ) to severe (ZZ) deficiency; could get disease and does carry 2 abnormal A1AT genes
Alpha-1 (SS) – It is unclear whether there is a risk for getting disease symptoms but does carry 2 abnormal A1AT genes (most studies do not show an increased risk for disease)
Alpha-1 (Null-Null) – Severe deficiency; people with NULL variants cannot make any A1AT and are at risk of serious disease