Defining familial longevity and developing a familial longevity score for unbiased epigenetic studies in a birth cohort.

Longevity accumulating in families has genetic and epigenetic components. To study early and unbiased epigenetic predictors of longevity prospectively, a birth cohort would be ideal. However, the original family longevity selection score (FLoSS) focuses on populations of elderly only. In the German birth cohort KUNO-Kids we assessed when information for such scores may be best collected and how to calculate an adapted FLoSS. A total of 551 families contributed to adapted FLoSS, with a mean score of -0.15 (SD 2.33). Adapted FLoSS ≥7 as a marker of exceptional longevity occurred in 3.3% of families, comparable to original FLoSS in elderly. An adapted FLoSS from data collectable postnatally may be a feasible tool to study unbiased epigenetic predictors for longevity.