Syndactyly (Syn = together; Dactylos = digits) is the most common limb defect mostly characterized by webbing of digits. It may be webbing with or without bony fusion and inherited mostly in autosomal dominant manner, although also reported as autosomal recessive, X-linked or isolated entity. It also shows diverse clinical and phenotypic heterogeneity and mostly observed as unilateral or bilateral and symmetrical or asymmetrical forms. Syndactyly mostly occurs either as an isolated anomaly or as a part of a complex syndrome (+150 syndromes). Here, non-syndromic syndactyly has been classified according to genetic and molecular basis. The non-syndromic syndactyly has been classified into nine different types. Up till now, the major genes identified to cause hereditary syndactyly are mainly involved in the sonic hedgehog pathway and zone of polarizing activity. The present review mostly focuses on summarizing the recent advances in molecular genetics, including known genes and loci responsible for non-syndromic syndactyly. The present review will contribute to the understanding of the pathogenesis underlying non-syndromic and syndromic syndactyly, improving clinical and molecular diagnosis; thus, making genetic counseling and prenatal testing easier in future.
Keywords: Limb malformation, syndactyly, digit webbing, molecular genetics.
Key words: Limb Malformation, Syndactyly, Digit webbing, Molecular genetics
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