Junctional epidermolysis bullosa (JEB) is an inherited condition that causes the skin to be extremely fragile leading to severe blistering. Small skin injuries and even simply rubbing or scratching can lead to blister formation and skin loss. Based on severity, JEB is classified into two main types, the generalized severe form (previously known as Herlitz JEB) and the generalized intermediate form (previously known as non-Herlitz JEB). This test identifies genetic variants in the LAMB3 gene which cause the generalized severe form.
LAMB3 provides instructions for a part of the laminin 332 protein. Laminin 332 is important for attaching the top layer of the skin (called the epidermis) to the layers underneath, which strengthens and stabilizes the skin. People affected with JEB make a defective or nonfunctional laminin 332 protein, resulting in a very fragile epidermis.
Take this test to find out whether you are a genetic carrier of a LAMB3 variant and are at risk of passing it to your children.
Genetic variants of several genes are associated with JEB. This test identifies genetic variants in the LAMB3 gene which generally cause the generalized severe form of JEB. JEB is inherited in an autosomal recessive pattern, which means two defective copies of the LAMB3 gene must be inherited in order for the disease to manifest.
LAMB3 variants account for about 70% of JEB cases, and the three variants included in this test account for approximately 48% of LAMB3-related JEB cases.
This test detects three genetic variants in the LAMB gene which cause JEB (usually the generalized severe form).
- rs80356682 A (R635X)
- rs80356680 A (R42X)
- rs80356681 A (Q243X)
Understanding your carrier status will help you understand the risk of passing a LAMB3 variant to your children.
Characteristic symptoms include:
- Fragile skin
- Severe blistering
- Recurrent infections due to scarring from extensive blistering
- Difficulty swallowing leading to undernourishment
- Difficulty breathing due to build up of scar tissue in the respiratory tract
- Other complications can include fusion of the fingers and toes, joint deformities, and alopecia
How It Works
Step 1: Sign up for a free DNA Access account.
Step 2: Upload your DNA markers to DNA Access.
Step 3: Log in to your account to access your results when they are ready.