Phenotypes associated with the disease synpolydactyly type 1 (OMIM:186000):
- 3-4 finger cutaneous syndactyly (HP:0011939): A soft tissue continuity in the A/P axis between fingers 3 and 4. Evidence: PCS. Frequency: 5/20. (PMID:9758628)
- Congenital onset (HP:0003577): A phenotypic abnormality that is present at birth. Evidence: PCS. (PMID:9758628)
- Short middle phalanx of the 5th finger (HP:0004220): Hypoplastic/small middle phalanx of the fifth finger. Evidence: IEA. (OMIM:186000)
- 4-5 toe syndactyly (HP:0004692): Syndactyly with fusion of toes four and five. Evidence: PCS. Frequency: 8/18. (PMID:9758628)
- 2nd-5th toe middle phalangeal hypoplasia (HP:0008083). Evidence: IEA. (OMIM:186000)
- Contracture of the proximal interphalangeal joint of the 5th finger (HP:0009185): Proximal interphalangeal (PIP) flexion deformity of the little finger. That is, the PIP joint of a little finger is bent (flexed) and cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement. Evidence: IEA. (OMIM:186000)
- Broad hallux (HP:0010055): Visible increase in width of the hallux without an increase in the dorso-ventral dimension. Evidence: PCS. (PMID:9758628)
- Y-shaped metacarpals (HP:0006042): Y-shaped metacarpals are the result of a partial fusion of two metacarpal bones, with the two arms of the Y pointing in the distal direction. Y-shaped metacarpals may be seen in combination with polydactyly. Evidence: IEA. (OMIM:186000)
- Finger syndactyly (HP:0006101): Webbing or fusion of the fingers, involving soft parts only or including bone structure. Bony fusions are referred to as "bony" Syndactyly if the fusion occurs in a radio-ulnar axis. Fusions of bones of the fingers in a proximo-distal axis are referred to as "Symphalangism". Evidence: IEA. (OMIM:186000)
- Clinodactyly of the 5th finger (HP:0004209): Clinodactyly refers to a bending or curvature of the fifth finger in the radial direction (i.e., towards the 4th finger). Evidence: TAS. (OMIM:186000)
- Mesoaxial hand polydactyly (HP:0006159): The presence of a supernumerary finger (not a thumb) involving the third or fourth metacarpal with associated osseous syndactyly. Evidence: TAS. (OMIM:186000)
- Postaxial foot polydactyly (HP:0001830): Polydactyly of the foot most commonly refers to the presence of six toes on one foot. Postaxial polydactyly affects the lateral ray and the duplication may range from a well-formed articulated digit to a rudimentary digit. Evidence: IEA. (OMIM:186000)
- Preaxial foot polydactyly (HP:0001841): Duplication of all or part of the first ray. Evidence: TAS. Frequency: Occasional (HP:0040283). (OMIM:186000)
- Autosomal dominant inheritance (HP:0000006): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele. Evidence: PCS. (PMID:9758628)
- 6 metacarpals (HP:0001501). Evidence: TAS. (OMIM:186000)