multiple synostoses syndrome 1 (SYNS1); synostoses, multiple, with brachydactyly; symphalangism-brachydactyly syndrome

Genetics

• autosomal dominant
• associated with defects in NOG gene
• different mutations in NOG can result in either tarsal-carpal coalition syndrome or multiple synostoses syndrome-1 in different families

Clinical manifestations

• tubular-shaped (hemicylindrical) nose with lack of alar flare
• otosclerotic deafness
• multiple progressive joint fusions beginning in the hand
  • begin in the 5th proximal interphalangeal joint in early childhood (or at birth in some individuals)
  • progress in an ulnar-to-radial & proximal-to-distal direction
  • with increasing age, ankylosis of other joints, including cervical vertebrae, hips, & humeroradial joints

More general terms

• multiple synostoses syndrome

Database

• OMIM: https://mirror.omim.org/entry/186500