Regression lines for telomere length according to age. The vertical axis represents the median telomere length in kilobytes. Lines in the figures indicate the first, tenth, 50th, 90th, and 99th percentiles of results from 400 normal control subjects. Patients with dyskeratosis congenita (DC) (red solid line), relatives with dyskeratosis congenita (red dashed line), non–dyskeratosis congenita patients (black long dashed line), and non–dyskeratosis congenita relatives (black short dashed line).