Hematologically Important Mutations: Leukocyte Adhesion Deficiency

Leukocyte adhesion deficiency (LAD) is an immunodeficiency caused by defects in the adhesion of leukocytes (especially neutrophils) to the blood vessel wall. As a result, patients with LAD suffer from severe bacterial infections and impaired wound healing. In LAD-I, mutations are found in INTG2, the gene that encodes the β subunit of the β2 integrins. In the rare LAD-II disease, the fucosylation of selectin ligands is disturbed, caused by mutations in the gene for a GDP–fucose transporter of the Golgi. This article summarizes all known patient mutations and polymorphisms in these genes.