# A statistical approach to distinguish telomere elongation from error in longitudinal datasets

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## Abstract

Telomere length and the rate of telomere attrition vary between individuals and have been interpreted as the rate at which individuals have aged. The biology of telomeres dictates shortening with age, although telomere elongation with age has repeatedly been observed within a minority of individuals in several populations. These findings have been attributed to error, rather than actual telomere elongation, restricting our understanding of its possible biological significance. Here we present a method to distinguish between error and telomere elongation in longitudinal datasets, which is easy to apply and has few assumptions. Using simulations, we show that the method has considerable statistical power (>80 %) to detect even a small proportion (6.7 %) of TL increases in the population, within a relatively small sample (*N* = 200), while maintaining the standard level of Type I error rate (α ≤ 0.05).

## Keywords

Telomere length Statistics Telomere shortening Within individual Aging Human## Notes

### Acknowledgments

MJPS is supported by the Natural Environment Research Council (J024597/1) (United Kingdom). SN is supported by the Rutherford Discovery Fellowship (New Zealand). GS is supported by a grant by The Netherlands Organisation for Scientific Research (452-10-012), granted to M. Mills.

## Supplementary material

## References

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