from the same individual in any single regression calculation were adjusted by dividing each weight by the sum of all the weights used in the calculation for that individual if the sum was greater than 1. Weights for sibs were adjusted to account for commonality of SNPs; i.e. since on average pairs of sibs share 50% of their genotype, the weights for pairs of non-identical sibs was multiplied by .75, and correspondingly for larger numbers of sibs. The bandwidth for the kernel (Epanechnikov) was taken as 0.6 to minimize the mean squared error, although the variation in the size of the error was less than 2% over the range of bandwidths from 0.4 to 0.8. All calculations were carried out in Matlab2014a (The MathWorks Inc. Natick, MA, USA) using the function glmfit().
