Hyperactive. Frequent alternation between forward and backward locomotion (shuttling). hp647 is a is a gain-of-function mutation identified as a suppressor of the 'fainter' motor defects of unc-80(e1069) mutants. Reference: Gao S, Elife. 2018 Jan 23:7:e29915. doi: 10.7554/eLife.29915. PMID: 29360035.