Effect of simple association of genotype (model 1) and models examining linkage disequilibrium without (model 2) or with (model 3) influences of parent of origin of T-allele. The joint hypothesis of linkage and association is examined by “within family” effects. β is given as effect of each additional T-allele (model 1 and between-family effects in models 2 and 3) or per additional T-allele above that expected, given parental genotype (within family effects, models 2 and 3). All models include random effect of nuclear family. Birth weight is adjusted for sex, gestational age at birth, birth year, and maternal diabetes.

Number is reduced as inheritance of offspring T-allele in triple heterozygote trios (mother, father, and child) cannot be defined.