Susceptibility to mycobacterial infections linked to X (X-linked susceptibility to mycobacterial disease) - Gen IKBKG.

Susceptibility to mycobacterial infections linked to X, is a disorder that causes an increased risk of infection with mycobacteria. Some of these mycobacteria behave as "opportunistic" because they do not cause disease in people with normal immune systems.

This process is due to mutations in the gene IKBKG, located on the long arm of chromosome X (Xq28). This gene encodes a subunit of IKK protein complex, a group of related proteins that regulates the activity of the kappa-B-nuclear factor. The nuclear factor kappa-B is a protein complex binds to DNA and controls the activity of other genes. The IKBKG protein plays a regulatory role in the IKK complex. Once the protein is activated IKBKG enable other proteins in the complex, which in turn activates and releases the nuclear factor-kappa-B. Activated factor then advances to the nucleus and binds DNA. The nuclear factor-kappa-B regulates the activity of multiple genes, including genes that control the body 's immune response and inflammatory reactions. Moreover, this factor seems to play a role in the signaling pathway that is critical for the formation of ectodermal tissues, including skin glands, hair, teeth, and sweat. It also protects the cell from apoptosis.

Mutations in the gene IKBKG leading to susceptibility to mycobacterial infections, alter the structure of the protein IKBKG. The defective protein alters certain signaling pathways within immune cells, preventing the immune system defends the body effectively against mycobacterial infection.

This disease is inherited in a recessive X - linked pattern in males, an altered copy of the gene in each cell is sufficient for the disease to be expressed. In women, a mutation would have to happen in both copies of the gene to express the disease. Because it is unlikely that women have two altered copies of this gene, males are affected by X - linked recessive disorders much more frequently than women. A feature of the X - linked inheritance is that fathers can not pass X - linked traits to their sons chromosome.

Tests in IVAMI: in IVAMI perform detection of mutations associated with susceptibility to mycobacterial infections linked to X through the complete PCR amplification of exons IKBKG gene, and subsequent sequencing.

Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).