3-Methylglutaconic Aciduria, Type Viii, also known as 3-methylglutaconic aciduria type 8, is related to 3-methylglutaconic aciduria, type viib and 3-methylglutaconic aciduria with cataracts, neurologic involvement and neutropenia. An important gene associated with 3-Methylglutaconic Aciduria, Type Viii is HTRA2 (HtrA Serine Peptidase 2). Affiliated tissues include brain and bone marrow, and related phenotypes are sensorineural hearing impairment and failure to thrive