Skinfold over toenail is pathognomonic for the popliteal pterygium syndrome in a Congolese family with large intrafamilial variability

Abstract

Key Clinical MessageWe report on three related Congolese popliteal pterygium syndrome (PPS) patients concordant only for the skinfold over the toenail. Mutation analysis revealed that the three affected individuals carried a heterozygous missense mutation in the Exon 4, NM_006147.2:c.250C>T; p.Arg84Cys. This is the first molecularly confirmed PPS family from central Africa.

Popliteal Pterygium Syndrome with Scrotal Agenesis

“…Popliteal pterygium syndrome (PPS) (OMIM #119500) has been described to be an autosomal dominant condition involving mutation in Interferon regulatory factor (IRF)-6 gene on chromosome 1q32 [1]. Abnormalities associated with it include cleft lip/palate, lower lip pits or cysts, syngnathia, congenital ankyloblepharon, scrotal and labial abnormalities, cryptorchidism, popliteal webbing, telipes equinovarus, syndactyly and nail anomalies [1,4]. Antenatal diagnosis by sequence analysis of the IRF6 gene in DNA extracted from amniocentesis or chorionic villus sampling can be done in cases of a positive family history where a disease causing mutation has been detected [2].…”

Microdeletion of the entire IRF6 gene in a Subsaharian African’s family with Van der Woude syndrome

“…It is an autosomal dominant condition with high penetrance, but with marked inter-and intrafamilial variation of phenotype (Cheney et al, 1986 (Gorlin, RJ an al., 2001). These facial anomalies are also seen in individuals with popliteal pterygium syndrome (PPS, OMIM 119500) which is characterized by pterygium in the popliteal region, ankyloblepharon filiforme, syngnathia, pyramidal skinfold overlying the nail of the hallux, syndactyly, oligodactyly, and skinfold over toenail (Mubungu et al, 2014, Schutte et al, 1993. Mutatios in two genes have been described in patients with Van der Woude syndrome, most commonly in the IRF6 gene (Sander et al, 1994, more rarely in the GRHL3 gene (Peyrard-Janvid et al, 2014).…”