Table 3.
Schizophrenia and bipolar disorder polygenic risk scores (PRSs) in the three diagnostic subgroups and in unaffected relatives v. controlsa
| Clinical subgroups | Schizophrenia PRS | Bipolar disorder PRS |
|---|---|---|
| PT = 0.05 | PT = 0.05 | |
| Schizophrenia/schizoaffective (n = 792) v. controls (n = 1472) | ||
| P-value | 6.1 × 10−39 | 9.2 × 10−08 |
| Variance explained, % | 10.3 | 1.6 |
| Bipolar disorder (n = 109) v. controls (n = 1058) | ||
| P-value | 6.2 × 10−06 | 6.5 × 10−03 |
| Variance explained | 3.4 | 1.2 |
| Other psychotic disorders (n = 267) v. controls (n = 1429) | ||
| P-value | 1.2 × 10−08 | 1.2 × 10−03 |
| Variance explained, % | 3.3 | 1.0 |
| Relatives (n = 552) v. controls (n = 1221) | ||
| P-value | 1.2 × 10−04 | 2.1 × 10−02 |
a.
Significance of the case–control PRS difference was analysed by standard logistic regression using different P-value thresholds (PT 5 × 10−08, 1 × 10−04, 0.05 and 1). Here, P-values and Nagelkerke's R2 obtained at PT = 0.05 are reported. Results at each one of the four different P-value thresholds (PT) are available in Supplementary Table 7. Logistic regression included the first three ancestry-based principal components and a cohort indicator as covariates. We report the proportion of the phenotypic variance explained by the risk polygenic score as measured by Nagelkerke's pseudo-R2.