(AB, AB), and so on. In total, there are six potential mating types: AA-AA, AA-AB, AA-BB, AB-AB, AB-BB, and BB-BB. Controlling for mating type conditions the estimate for b1 (the effect of a particular SNP on BMI) on the likelihood of an individual inheriting a particular allele from either or both parents. The most important aspect of this model is that the use of trios enables researchers to look at distributions of alleles within the family, nearly eliminating the risk of population stratification. This model is comparable to the FBAT approach (Laird et al. 2000; Laird and Lange 2006), which has been successfully used to identify SNPs linked to obesity (Herbert et al. 2006). (2)E(Yi∣X,Z)=b0m+b1Xi+b2mZi+b3ZiXi.
