SLC6A4 and Abnormal autonomic nervous system physiology: Our results are also in need of replication with a tracer that is selective to SERT, such as PET scans using [11C]-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)-benzonitrile, or [11C]DASB [43], to draw clearer conclusions about the specific involvement of serotonergic degeneration in autonomic dysfunction.