Symptoms and Signs
- Limb findings: extensive web from behind the knee to the heel, malformed toenails, webbed toes
- Facial findings: cleft palate with or without cleft lip, pits in the lower lip, fibrous bands in the mouth (syngnathia), tissue connecting upper and lower eyelids
- Genital findings: hypoplasia of the labia majora, malformation of the scrotum, cryptorchidism
- Other findings: popliteal pterygium, distinct toe/nail abnormality, syndactyly

Genetics
- Autosomal dominant inheritance
- Mutation of the IRF6 gene
- Most cases are sporadic, suggesting new mutations
- Lethal PPS and PPS with Ectodermal Dysplasia are rare autosomal recessively inherited conditions
- Lethal PPS is differentiated by microcephaly, corneal aplasia, ectropion, bony fusions, hypoplastic nose, and absent thumbs

Relationship to Van der Woude syndrome
- Van der Woude syndrome and PPS are allelic variants of the same condition
- PPS includes all the features of VDWS, plus additional abnormalities
- Additional abnormalities in PPS include popliteal pterygium, syngnathia, distinct toe/nail abnormality, syndactyly, and genito-urinary malformations

Diagnosis (currently empty)

Treatment (currently empty)

Epidemiology
- PPS has been diagnosed in several ethnic groups, including Caucasian, Japanese, and sub-Saharan African
- Males and females are equally likely to have the syndrome
- Incidence rate is difficult to estimate but is less than 1 in 300,000