Although there is no direct pathological evidence that Hapln2 is a integral constituent of LB in PD, Hapln2 has been recently shown to be accumulated in the neurofibrillary tangle of Alzheimer's brain (Bandopadhyay, 2016), indicating that Hapln2 can be the part of protein deposition process involved in pathogenesis of both AD and PD. This evidence concerns the gene HAPLN2 and Alzheimer disease.