What are the genetic changes related to leukocyte adhesion deficiency type 1 ?
Mutations in the ITGB2 gene cause leukocyte adhesion deficiency type 1. This gene provides instructions for making one part (the 2 subunit) of at least four different proteins known as 2 integrins. Integrins that contain the 2 subunit are found embedded in the membrane that surrounds white blood cells (leukocytes). These integrins help leukocytes gather at sites of infection or injury, where they contribute to the immune response. 2 integrins recognize signs of inflammation and attach (bind) to proteins called ligands on the lining of blood vessels. This binding leads to linkage (adhesion) of the leukocyte to the blood vessel wall. Signaling through the 2 integrins triggers the transport of the attached leukocyte across the blood vessel wall to the site of infection or injury.  ITGB2 gene mutations that cause leukocyte adhesion deficiency type 1 lead to the production of a 2 subunit that cannot bind with other subunits to form 2 integrins. Leukocytes that lack these integrins cannot attach to the blood vessel wall or cross the vessel wall to contribute to the immune response. As a result, there is a decreased response to injury and foreign invaders, such as bacteria and fungi, resulting in frequent infections, delayed wound healing, and other signs and symptoms of this condition.