Alpha 1-antitrypsin phenotypes in patients with abdominal aortic aneurysms.

The alpha 1-antitrypsin phenotypes were determined in 47 patients with abdominal aortic aneurysms. The MM phenotype was present in 85%, the MS phenotype in 4%, the MZ phenotype in 11%, and the ZZ phenotype not present in any patients. The MZ phenotype occurred significantly more often in patients with aneurysms than would be expected in the general population. The current data would support a genetic mechanism of either autosomal-dominant or multifactorial influences but not an X-linked mechanism for families with a history of abdominal aortic aneurysms.