Figure 1
From: Environmental effects on brain functional networks in a juvenile twin population
Schematic illustration of genetic and environmental analysis pipeline. For each FC metric, separately for MZ and DZ twin pairs, we computed the linear partial correlation coefficient between the selected feature values obtained from each twin in each pair, at net of the effects of age and sex. We obtained zygosity-specific correlations (\({r}_{MZ}\) and \({r}_{DZ}\)) for each FC metric at brain-, node- and link-level. Genetic and environmental analysis was performed on the FC metrics associated with \({r}_{MZ}>{r}_{DZ}>0\). Three main scenarios were distinguished based on \(\frac{{r}_{MZ}}{{r}_{DZ}}\) ratio: ADE or ACE twin model applicability and the analysis of nonadditive genetic effect of epistasis. The estimate of “broad-sense” or “narrow-sense” heritability was extracted for the FC metrics that verified respectively ADE or ACE twin model applicability condition. FC: functional connectivity. MZ: monozygotic. DZ: dizygotic. \({\mathrm{r}}_{\mathrm{DZ}}\): intra-pair phenotypic correlation in DZ pairs. \({r}_{MZ}\): intra-pair phenotypic correlation in MZ pairs.
