STYXL1 and neurodegenerative disease: MK-STYX is highly expressed in human hippocampus (Boycott and Wassle, 1991; Hubbard et al., 2012), and a missense mutation of MK-STYX results in intellectual disability and epilepsy (Boycott and Wassle, 1991), highlighting the timeliness of this study and the emergence of MK-STYX as an important candidate to understand the etiology of various neurodegenerative diseases.