Clinical features
All patients with PVRL4mutations identified so far, present partial cutaneous syndactyly (most often between the 2nd–3rd toes and the 3rd–4th fingers), together with an ectodermal phenotype of sparse, fragile scalp hair, eyebrows, and eyelashes with progressive alopecia to total loss by the fourth decade; and dental anomalies (widely spaced conical/peg-shaped teeth with enamel hypoplasia, delayed eruption, hypodontia/anodontia). Other features, which are not present in all patients, include age-progressive palmoplantar hyperkeratosis, hypoplastic nails, and reduced or absent sweat glands.
Prevalence
The PVRL4-related syndrome is rare. Its prevalence is unknown, only a few families have been reported.
Genetic Counselling
Mutations in PVRL4are inherited in an autosomal recessive manner. Affected individuals are typically born to unaffected carrier parents; consanguinity may be present in some families. The condition is exceptionally rare. Carrier testing for at-risk relatives and prenatal or preimplantation genetic testing are technically feasible once the familial variants are identified.
PVRL4