Question: What are the genetic changes related to X-linked hyper IgM syndrome ?
Answer: Mutations in the CD40LG gene cause X-linked hyper IgM syndrome. This gene provides instructions for making a protein called CD40 ligand, which is found on the surface of immune system cells known as T cells. CD40 ligand attaches like a key in a lock to its receptor protein, which is located on the surface of immune system cells called B cells. B cells are involved in the production of antibodies, and initially they are able to make only IgM antibodies. When CD40 ligand and its receptor protein are connected, they trigger a series of chemical signals that instruct the B cell to start making IgG, IgA, or IgE antibodies. CD40 ligand is also necessary for T cells to interact with other cells of the immune system, and it plays a key role in T cell differentiation (the process by which cells mature to carry out specific functions). Mutations in the CD40LG gene lead to the production of an abnormal CD40 ligand or prevent production of this protein. If CD40 ligand does not attach to its receptor on B cells, these cells cannot produce IgG, IgA, or IgE antibodies. Mutations in the CD40LG gene also impair the T cell's ability to differentiate and interact with other immune system cells. People with X-linked hyper IgM syndrome are more susceptible to infections because they do not have a properly functioning immune system.
Source: GHR

Question: What are the treatments for X-linked hyper IgM syndrome ?
Answer: These resources address the diagnosis or management of X-linked hyper IgM syndrome: - Gene Review: Gene Review: X-Linked Hyper IgM Syndrome - Genetic Testing Registry: Immunodeficiency with hyper IgM type 1 - MedlinePlus Encyclopedia: Immunodeficiency Disorders These resources from MedlinePlus offer information about the diagnosis and management of various health conditions: - Diagnostic Tests - Drug Therapy - Surgery and Rehabilitation - Genetic Counseling - Palliative Care
Source: GHR