We took advantage of the known complete loss-of-function alleles, *2 and *4, to estimate parameters to build a model predicting phenotype by genotype. Parameter estimates for each haplotype, gender and smoking status are summarized in Table 6, as well as p-values comparing each variable to 0 (no activity) or the reference haplotype (*1B, the most common haplotype) in the multiplicative model. This model including all parameter estimates, describes the phenotype, D2-cotinine: (D2-nicotine + D2-cotinine), in the dataset with an adjusted R2 of 0.732.
