Short-Rib Thoracic Dysplasia 3 with or without Polydactyly

**Semantic type:** Disease or Syndrome

**Definition:** An autosomal recessive type of short rib-polydactyly syndrome caused by mutation(s) in the DYNC2H1 gene, encoding cytoplasmic dynein 2 heavy chain 1. Additionally, there is evidence that it may be caused by digenic biallelic mutation in DYNC2H1 and in NEK1 (the latter encoding serine/threonine-protein kinase Nek1). It is characterized by a constricted thoracic cage, short ribs, and a 'trident' appearance of the acetabular roof. Polydactyly may or may not be present.

**Synonyms:** - SRTD3