Telomere length and possible link to X chromosome
Tim S Nawrot1, Jan A Staessen, Jeffrey P Gardner
1Study Coordinating Centre, Laboratory of Hypertension, Department of Molecular and Cardiovascular Research, University of Leuven, Campus Gasthuisberg, Herestraat 49, B-3000 Leuven, Belgium.
Lancet (London, England)
|February 21, 2004
Summary
Telomere length, a marker of cellular aging, appears to be inherited in an X-linked manner. This suggests that the aging process itself may be an X-linked trait.
Area of Science:
- Genetics
- Human Biology
- Aging Research
Background:
- Telomere length reflects cellular replicative history and is linked to clinical aging markers.
- Previous twin studies suggest telomere length is familial, but its inheritance pattern remains unclear.
Purpose of the Study:
- To investigate the mode of inheritance for telomere length in humans.
Main Methods:
- Terminal restriction fragment (TRF) length was measured in DNA from white blood cells.
- Data were collected from a family-based cohort (Flemish Study on Environment, Genes, and Health Outcomes).
Main Results:
- No significant correlation in TRF length was found between spouses or between fathers and sons.
- Strong correlations in TRF length were observed between fathers and daughters, mothers and children, and among siblings.
Conclusions:
- X-linked inheritance is the most likely explanation for the observed telomere length correlations.
- These findings suggest that aging may be an X-linked trait, pending further confirmation.
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Overview
01:19X-linked Traits
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02:27Trihybrid Crosses
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02:32X and Y Chromosomes
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