Netherton Syndrome is caused by a defect or a change in the SPINK-5 gene. This gene is located on the long arm of the fifth chromosome, 5q. This gene should take care of the production of the LEKTI protein. This protein is needed in one of the outer layers of the skin, the epidermis.
People who have Netherton’s Syndrome don’t have the LEKTI protein. This protein is needed as a cement between the skin cells. The lack of LEKTI causes a red and scaly skin. The skin renews itself too fast. The barrier function of the skin is also damaged. The ability to protect against infections is increased, and it makes the body easily lose its fluids. Dehydration is a well known complication. The damaged barrier also makes it easier for medication in ointments to enter the body. For example, a steroid ointment which is used on this permeable skin can give complications inside the body.
LEKTI is needed for normal hair growth.
LEKTI is also known to be part of the thymus, the organ that makes our immune cells. Therefore people with Netherton have often allergies and they easily get bacterial or viral infections.
The lack of LEKTI causes the characteristic symptoms of Netherton Syndrome: the red and scaly skin, the bamboo hair and the vulnerability for infections and allergies.