The observed frequency of subjects with one or more clonal mosaic anomalies detected (‘mosaic status’) is shown in Figure 5 and Supplementary Table 4. It is low (< 0.5%) in subjects less than 50 years old, but increases thereafter to 2.7% in subjects over 80. The mosaic frequency is 0.2% in both the 0–14 (15/8535) and 15–29 year old group (16/6739), despite the fact that approximately half of the 0–14 year old subjects have a phenotypic abnormality (non-syndromic cleft lip/palate, prematurity or low birth weight). Excluding subjects less than 15 years old, in multiple logistic regression of mosaic status on age at DNA sampling, and adjusting for several covariates (study, sex, DNA source, and ethnicity), age is a highly significant predictor of mosaic status (p = 2 × 10−16, odds ratio=1.05, 95% confidence interval (CI)=1.04 – 1.07). Among the covariates, only study is significant (p=0.01) and a subsequent test of age-by-study interaction was not significant. It is notable that DNA source (92% from blood, 8% from saliva/buccal swabs) was not a significant predictor (p=0.45). When only blood samples are analyzed,
