Interstitial deletion of 7q31.32 → q33 secondary to a paracentric inversion of a maternal chromosome 7

Review of literature: genes related to postaxial polydactyly

BACKGROUND

Postaxial polydactyly (PAP) is one of the commonest congenital malformations and usually is associated to several syndromes. There is no primary investigational strategy for PAP cases with single gene disorder in literature. PAP cases with single gene disorder can be classified according to common pathways and molecular basis. Molecular classification may help in diagnostic approach.

MATERIALS AND METHODS

All single gene disorders associated with PAP reported on PubMed and OMIM are analyzed and classified according to molecular basis.

RESULTS

Majority of genes related to cilia structure and functions are associated with PAP, so we classified them as ciliopathies and non-ciliopathies groups. Genes related to Shh-Gli3 pathway was the commonest group in non-ciliopathies.

CONCLUSION

Genes related to cilia are most commonly related to PAP due to their indirect relationship to Shh-Gli3 signaling pathway. Initially, PAP may be the only clinical finding with ciliopathies so those cases need follow up. Proper diagnosis is helpful for management and genetic counseling. Molecular approach may help to define pleiotropy.