In a subsequent series of analyses we investigated possible discrepancy in the percentage of variance explained by SNPs and variance explained by latent additive genetic influences estimated in twin and family studies. We mimicked the conventional AE-model (that is, estimation of additive genetic factors and environmental factors) using the entire Australian sample, including close relatives (for example, MZ/DZ twin pairs, full sibs, parent-offspring pairs and cousins), that is, no cutoff in genetic similarity between individuals was applied. In twin and family studies, estimates of heritability are based on the relationship between phenotypic resemblance and expected genetic similarity based on pedigree information (for example, MZ twin pairs are expected to share 100% of their genetic material, whereas DZ twins, full sibs and parent-offspring pairs are expected to share 50% of their genetic material). SNP data, however, provide us with estimates of the realized genetic similarity, which vary around the expected values from pedigrees (See Supplementary Information Figure S2). The genetic variation around the expected values (for example, 0, 50 or 100%) is not captured by pedigree studies but can be captured
