What gene is involved?
PVRL4makes nectin-4, a “cell-to-cell glue” (a cell-adhesion molecule) that sits at the contacts between neighboring cells and helps them stick together and organize. It connects inside the cell to the actin skeleton and helps tissues form proper layers and shapes.
How do changes in PVRL4cause the condition?
Most families have two faulty copies of the gene (autosomal recessive). These changes usually reduce or eliminate nectin-4, so cells don’t adhere and coordinate as they should during early development of skin, hair, teeth, and fingers/toes, leading to webbing (syndactyly), hair loss, and dental differences.
Anything else about nectin-4?
Outside this rare inherited condition, nectin-4 levels can be high in some cancers and can be released in a soluble form by an enzyme (ADAM17). It also serves as a receptor used by measles virus to move through airway lining cells. These points help scientists understand what the protein does but are separate from the inherited syndrome.
Testing implications
Diagnosis relies on genetic testing of PVRL4. Once the family’s changes are known, carrier testing and reproductive options are available.
PVRL4