5-HTTLPR status predictive of neocortical 5-HT4 binding assessed with [11C]SB207145 PET in humans

► We evaluate if the 5-HTTLPR variant predicts serotonin 4 receptor (5-HT4) binding. ► We assess 5-HT4 binding with [11C]SB207145 PET in 47 healthy human volunteers. ► 5-HTTLPR status significantly predicts neocortical [11C]SB207145 binding. ► S allele carriers show 9% reduced binding across neocortex versus LL homozygotes. ► This further suggests that 5-HTTLPR affects 5-HT neurotransmission in adult humans.