DNAH5  Dynein heavy chain 5, axonemal is a protein that in humans is encoded by the "DNAH5" gene. The DNAH5 gene is a protein-coding gene.1 It provides the instructions for synthesizing a protein that belongs to a microtubule-associated protein complex made of heavy, light and intermediate chains.2 The DNAH5 gene is responsible for making the heavy chain 5, found within the outer dynein arms of cilia.1 It will function as a force generating protein by using ATP, producing the power stroke for cilia.3   During early development, the cilia found on the primitive node will beat in a directional pattern, sending signaling molecules to the left, this process will begin to establish the internal left-right asymmetry.3 Mutations of the DNAH5 gene are linked to primary ciliary dyskinesia, an autosomal recessive disorder.4 This X-linked disorder is characterized by recurrent respiratory infections, infertility, and abnormal organ placement.1 Non-functional DNAH5 proteins have been identified in individuals with primary ciliary dyskinesia and randomized left-right asymmetry.4