Isolated or nonsyndromic polydactyly – GLI3 gene.

Polydactyly is usually a manifestation of some syndromes such as acrocallosal syndrome, Greig cephalopolysyndactyly syndrome or Pallister-Hall syndrome. However, in some cases it can be an isolated manifestation without it existing along with other signs or symptoms.

Polydactyly is usually related to mutations of the GLI3 gene. Mutations of this gene can cause various forms of isolated polydactyly. These forms include postaxial polydactyly type A (PAP-A) and type A/B (PAP-A/B), which are characterized by an additional digit next to the little finger or small toe. GLI3 gene mutations can also cause type IV preaxial polydactyly (PPD-IV), which is characterized by additional digits next to the thumb or next to the big toe and skin fusion between some hand fingers and feet toes (cutaneous syndactyly). Polydactyly PPD-IV may also include additional digits in other positions on the hands or feet. The polydactyly pattern seen with PPD-IV is similar to that of Greig´s cephalopolysindactyly syndrome, and some researchers suggest that PPD-IV may be a very mild form of that syndrome.

Tests performed in IVAMI: in IVAMI we perform the detection of mutations associated with isolated or nonsyndromic polydactyly, by means of the complete PCR amplification of the exons of the GLI3 gene, and their subsequent sequencing.

Recommended samples: non-coagulated blood obtained with EDTA for separation of blood leucocytes, or a card with a dried blood sample (IVAMI can mail the card to deposit the blood sample).