Controversy of TMEM230 Associated with Parkinson's Disease.

Parkinson's disease (PD) is a common neurodegenerative disease with movement disorders including resting tremor, bradykinesia, rigidity, and postural instability. The key pathological features of PD are selective loss of dopaminergic (DA) neurons in substantial nigra and the presence of Lewy bodies (LBs). Mutations in TMEM230 (transmembrane protein 230) have been recently reported to play a pathological role and contribute to PD pathogenesis. TMEM230 gene encodes two isoforms of TMEM230 proteins, isoform I (183 amino acids) and isoform II (120 amino acids). The function of TMEM230 is not clear, but it may be involved in vesicle trafficking and recycling, autophagy, protein aggregation, and cell toxicity. There are four reported PD-linked TMEM230 mutations (p.Y92C, p.R141L, p.*184Wext*5, p.*184PGext*5). TMEM230-linked PD cases exhibit late-onset, good-response to levodopa, and typical clinical features of sporadic PD with DA neuronal loss in substantial nigra and Lewy body pathology. In this mini review, we recap the current literature of TMEM230 in genetic, neurobiological, and pathological studies in order to further understand the potential roles of TMEM230 in PD pathogenesis.