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Genetic and Rare Diseases Information Center (GARD)

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Syndactyly type 3

Other Names for this Disease
  • Ring and little finger syndactyly
  • SDTY3
  • Syndactyly of fingers four and five
  • Syndactyly of the ring and little finger
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What is syndactyly type 3?

How is syndactyly type 3 inherited?

What is syndactyly type 3?

Syndactyly type 3 (SD3) is a limb abnormality present at birth that is characterized by complete fusion of the 4th and 5th fingers on both hands. In most cases only the soft tissue is fused, but in some cases the bones of the fingers (distal phalanges) are fused. There is evidence that SD3 is caused by mutations in the GJA1 gene, which has also been implicated in a condition called oculodentodigital dysplasia. SD3 is the characteristic digital abnormality in this condition. SD3 is inherited in an autosomal dominant manner.[1]
Last updated: 6/3/2013

How is syndactyly type 3 inherited?

Syndactyly type 3 has been shown to be inherited in an autosomal dominant manner.[1] This means that having only one mutated copy of the causative gene is sufficient to cause the condition. When an individual with an autosomal dominant condition has children, each child has a 50% (1 in 2) chance of inheriting the mutated gene and a 50% chance of inheriting the normal gene and being unaffected.
Last updated: 6/3/2013

  1. Syndactyly type 3. Orphanet. October 2010; Accessed 6/3/2013.