KIF6 is a kinesin-9 family motor protein that functions primarily in ciliary cargo transport and motility. KIF6 contains ATP hydrolysis activity and displays authentic microtubule-based motor activity in vitro, with its ciliary localization strictly requiring ATPase function 1. The protein forms puncta that move bidirectionally along ciliary axonemes, distinct from the regional oscillation pattern of its paralog KIF9 1. KIF6 is essential for coordinated ciliary beat in mammalian ependymal tissues and cerebrospinal fluid flow; Kif6-deficient mice develop severe hydrocephalus with high mortality 1. In spermatogenesis, Kif6 deficiency causes male infertility through oligozoospermia and defective sperm forward motility 1. Clinically, the KIF6 Trp719Arg polymorphism has been extensively studied in coronary heart disease (CHD) susceptibility. Meta-analyses show conflicting results: prospective studies in Caucasians demonstrate that the 719Arg allele increases CHD risk 2, while the largest pooled analysis of 50 studies found no significant association 3. The 719Arg allele notably increases vulnerability to LDL cholesterol, enhancing statin responsiveness 4. In statin-treated patients, ArgTrp and ArgArg carriers show increased major adverse cardiovascular events compared to TrpTrp carriers 5, despite significant cardiovascular benefit from statin therapy across all genotypes.