rs28935469

Description

The c.620C>T;p.(Pro207Leu) missense variant has been observed in affected individual(s) and ClinVar contains an entry for this variant (ClinVar ID: 11755; OMIM: 300017.0009; PMID: 12612583; 31942422; 16538226) - PS4.The variant is located in a mutational hot spot and/or critical and well-established functional domain (CH domain; PMID: 15917206) - PM1. This variant is not present in population databases (rs28935469, gnomAD; ABraOM no frequency - http://abraom.ib.usp.br/) - PM2. The variant co-segregated with disease in multiple affected family members (PMID: 12612583; 31942422; 16538226) - PP1_moderate. Multiple lines of computational evidence support a deleterious effect on the gene or gene product - PP3. In summary, the currently available evidence indicates that the variant is pathogenic.

The FLNA c.620C>T; p.Pro207Leu variant (rs28935469) has been described in individuals with otopalatodigital (OPD) syndrome type I (OPD1), and has shown to segregate with disease in males in at least 2 families (Robertson 2003). It contains an entry in ClinVar (Variation ID: 11755) and is absent from general population databases (1000 Genomes Project, Exome Variant Server, and Genome Aggregation Database), indicating it is not a common polymorphism. The proline at codon 207 is highly conserved, and computational algorithms (PolyPhen-2, SIFT) predict that this variant is deleterious. This variant is located in a calponin homology domain portion of the actin-binding domain, and several variants within this region are associated with OPD syndrome type I and type II, indicating that this domain is likely important for protein function (Hidalgo-Bravo 2005, Kondoh 2007, Marino-Enriquez 2007, Robertson 2003, Sankararaman 2013). Based on available information, this variant is considered pathogenic. REFERENCES Hidalgo-Bravo A et al. A novel filamin A D203Y mutation in a female patient with otopalatodigital type 1 syndrome and extremely skewed X chromosome inactivation. Am J Med Genet A. 2005 Jul 15;136(2):190-3. Kondoh T et al. A Japanese case of oto-palato-digital syndrome type II: an apparent lack of phenotype-genotype correlation. J Hum Genet. 2007;52(4):370-3. Marino-Enriquez A et al. Otopalatodigital syndrome type 2 in two siblings with a novel filamin A 629G>T mutation: clinical, pathological, and molecular findings. Am J Med Genet A. 2007 May 15;143A(10):1120-5. Robertson S et al. Localized mutations in the gene encoding the cytoskeletal protein filamin A cause diverse malformations in humans. Nat Genet. 2003 Apr;33(4):487-91. Sankararaman S et al. Otopalatodigital syndrome type 2 in a male infant: A case report with a novel sequence variation. J Pediatr Genet. 2013 Mar;2(1):33-6.