We investigated the influence of age at onset on the frequency of de novo mutations. After stratifying patients by age at onset ≤ 18, we observed a significantly higher rate of de novo CNVs in early-onset BD (p = 0.006, OR = 6.3 [1.7,22.6], Table 2). This difference was also nominally significant (p = 0.03) based on a survival analysis comparing AAO in subjects with or without a de novo CNV (Figure 3A). By contrast, we did not observe an effect of AAO on the frequency of de novo mutations in schizophrenia (Table 2, Figure 3B).
