be in positive linkage disequilibrium with the del and A alleles associated with low DBH plasma levels and paranoia in the Cubells et al. (2000) study (Zabetian et al. 2003). A controlled laboratory study was later conducted in which 31 cocaine-using volunteers acutely self-administered intravenous doses of the cocaine (0, 8, 16, and 32 mg/70 kg body weight) over four sessions (Kalayasiri et al. 2007). The previously identified −1021C→T polymorphism was tested for association with cocaine-induced paranoia, and the low DBH plasma level T/T genotype group reported higher paranoia when compared to the C/T and C/C groups.
