When genotype and gender are considered in an additive model, we find the CHRM2 TT genotype confers an increase in odds for having a low P300 trajectory of 2.32 (p = 0.054), while being male increases the odds to 2.84 (p=0.036) with the multiplicative effect of having a TT genotype and being male resulting in an increased odds of 6.58 (p=0.004) of having a low P300 trajectory. This relationship was seen only in the 8–12 age range.
