X-linked severe combined immunodeficiency (SCID) is an inherited disorder of the immune system that occurs almost exclusively in males. Children with X-linked SCID are prone to recurrent and persistent infections because they lack the necessary immune cells to fight off certain bacteria, viruses, and fungi.
Variants (also known as mutations) in the IL2RG gene cause X-linked SCID. The IL2RG gene provides instructions for making a protein that is critical for normal immune system function. This protein is necessary for the growth and maturation of developing immune system cells called lymphocytes. Lymphocytes defend the body against potentially harmful invaders, make antibodies, and help regulate the entire immune system. Variants in the IL2RG gene prevent these cells from developing and functioning normally. Without functional lymphocytes, the body is unable to fight off infections.
X-linked SCID is the most common form of a group of severe combined immunodeficiency disorders. This group of disorders can be caused by variants in more than 20 genes. The incidence of all severe combined immunodeficiency disorders is 1 in 60,000 newborns and it is estimated that one-quarter to one-third of these cases are X-linked SCID.
This condition is inherited in an X-linked recessive pattern. The gene associated with this condition is located on the X chromosome, which is one of the two sex chromosomes. In males (who have only one X chromosome), one altered copy of the gene in each cell is sufficient to cause the condition. In females (who have two X chromosomes), a variant would have to occur in both copies of the gene to cause the disorder. Because it is unlikely that females will have two altered copies of this gene, males are affected by X-linked recessive disorders much more frequently than females. A characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.
Morton Cowan is a Pediatric Allergy and Immunologist and a Pediatrics expert in San Francisco, California. Cowan has been practicing medicine for over 53 years and is rated as an Elite expert by MediFind in the treatment of X-Linked Severe Combined Immunodeficiency. He is also highly rated in 8 other conditions, according to our data. His top areas of expertise are Severe Combined Immunodeficiency (SCID), Bare Lymphocyte Syndrome, Omenn Syndrome, and X-Linked Severe Combined Immunodeficiency. He is licensed to treat patients in California.
Adrian Thrasher practices in London, United Kingdom. Thrasher is rated as an Elite expert by MediFind in the treatment of X-Linked Severe Combined Immunodeficiency. He is also highly rated in 39 other conditions, according to our data. His top areas of expertise are Wiskott-Aldrich Syndrome, X-Linked Severe Combined Immunodeficiency, Severe Combined Immunodeficiency (SCID), Bone Marrow Transplant, and Liver Transplant.
David Rawlings is a Pediatric Allergy and Immunologist and a Pediatric Rheumatologist in Seattle, Washington. Rawlings has been practicing medicine for over 39 years and is rated as an Elite expert by MediFind in the treatment of X-Linked Severe Combined Immunodeficiency. He is also highly rated in 7 other conditions, according to our data. His top areas of expertise are X-Linked Severe Combined Immunodeficiency, Wiskott-Aldrich Syndrome, Severe Combined Immunodeficiency (SCID), and Immunodeficiency with Hyper IgM Type 1. He is licensed to treat patients in Washington. Rawlings is currently accepting new patients.
Summary: Severe combined immunodeficiency disorder (SCID) is a heterogeneous group of inherited disorders characterized by a profound reduction or absence of T lymphocyte function, resulting in lack of both cellular and humoral immunity. SCID arises from a variety of molecular defects which affect lymphocyte development and function. The most common form of SCID is an X-linked form (SCID-X1), which account...
Summary: This study will evaluate patients with abnormal immune function that results in recurrent or unusual infections or chronic inflammation. This may include inherited conditions, such as X-linked severe combined immunodeficiency (XSCID), chronic granulomatous disease (CGD), and leukocyte adhesion deficiency (LAD), or conditions resulting from outside factors, such as graft-versus-host disease (GVHD)....
Published Date: March 18, 2022Published By: National Institutes of Health