Given there was a helpful answer to what was the biological cause of schizophrenia what kind of answer would that answer have to be?
Holding that 1000’s of common alleles each of which have an only miniscule impact lead to schizophrenia is a kind of answer that has absolutely no treatment implications. Focusing on an allele of this or that gene in isolation has absolutely no treatment implications. Epigenetic changes that affect a gene in isolation from other genes have no treatment implications. Focusing on this or that biological anomaly has absolutely no treatment implications. There are hundreds of biologically anomalies in schizophrenia apparently all disconnected from each other.
A helpful answer must point to the headwaters of genetic or epigenetic dysregulations. A transcription factor could affect translation of many genes and at times various researchers have pointed to various transcription factors as being implicated in schizophrenia. Funding research on transcription factors in connection to schizophrenia makes sense in terms of translational medicine.
Another answer that would be helpful in terms of treatment is an answer that pointed to a biological pathway that could widely dysregulate epigenetic mechanisms. Dysregulation of the TCA cycle via dysregulation of aconitase 1 and the 2-oxogultarate dehydrogenase complex could widely dysregulate epigenetic mechanisms.