Table 1 Inflation of heritability estimates and their corrected values for select UK Biobank traits.

From: Assortative mating biases marker-based heritability estimators

Phenotype

\(r\)

\(n\)

\({\hat{h}}_{{{{{{\rm{HE}}}}}}}^{2}\) [s.e.]

\({\hat{h}}_{{{{{{\rm{REML}}}}}}}^{2}\) [s.e.]

\({\hat{h}}_{{{{{{\rm{\infty }}}}}}}^{2}\) [s.e.]

\({\hat{h}}_{0}^{2}\) [s.e.]

\({\hat{h}}_{{{{{{\rm{HE}}}}}}}^{2}/{\hat{h}}_{{{{{{\rm{\infty }}}}}}}^{2}\) [s.e.]

Body mass indexa

0.228

334,429

0.257 [3.15e−3]

0.256 [2.29e−3]

Bone mineral densitya,b

191,330

0.277 [4.37e−3]

0.295 [3.28e−3]

Height

0.240

334,798

0.567 [4.68e−3]

0.525 [2.22e−3]

0.499 [4.23e−3]

0.467 [3.37e−3]

1.14 [8.70e−4]

Years of education

0.412

332,198

0.174 [2.64e−3]

0.155 [2.01e−3]

0.163 [2.46e−3]

0.153 [2.06e−3]

1.07 [9.46e−4]

  1. Spousal correlations (\(r\)) as previously reported in British cohorts2,4 and heritability estimates for selected UK Biobank phenotypes (\(n\) denotes sample size). Height and years of education were selected a priori on the basis of previous evidence for primary phenotypic AM whereas body mass index and bone mineral density were selected a priori as negative controls. Assuming equilibrium, the equilibrium (\({\hat{h}}_{{{{{{\rm{\infty }}}}}}}^{2}\)) and panmictic (\({\hat{h}}_{0}^{2}\)) heritability estimates (defined in Eq. 3) provide unbiased estimates of the present day and panmictic heritabilites, respectively. Under disequilibrium, they respectively provide probabilistic lower bounds, with the HE regression (\({\hat{h}}_{{{{{{\rm{HE}}}}}}}^{2}\)) and REML (\({\hat{h}}_{{{{{{\rm{REML}}}}}}}^{2}\)) estimates providing complementary upper bounds. The ratio \({\hat{h}}_{{{{{{\rm{HE}}}}}}}^{2}/{\hat{h}}_{{{{{{\rm{\infty }}}}}}}^{2}\) reflects the extent to which HE regression overestimates the true heritability under the assumption of equilibrium.
  2. aAdjusted equilibrium and panmictic heritability estimates omitted for negative control traits.
  3. bNo estimates of the phenotypic mating correlation for bone mineral density were available.