1Department of Anthropology, Northwestern University, 2Cells 2 Society: the Center for Social Disparities and Health, Institute for Policy Research, Northwestern University, 3Office of Population Studies Foundation, University of San Carlos, 4Division of Endocrinology, Metabolism and Molecular Medicine, Department of Medicine, Northwestern University Medical School, 5Center for Genetic Medicine, Northwestern University
Saturday 4:45-5:00, Parlors
Telomeres are repetitive DNA sequences found at the ends of chromosomes that shorten with age in proliferating human tissues. This shortening is implicated in senescence, with previous work suggesting that shorter telomere length (TL) impairs immune and cardiovascular function and results in increased mortality.
Contrary to the TL shortening which occurs with age in most proliferating tissues, several studies report that TL in sperm of older men tend to be longer than in younger men and, correspondingly, that offspring of older men inherit longer TL. We recently hypothesized that this paternal age effect on offspring TL is a mechanism for transmitting information about environmental experiences in recent generations to adaptively adjust offspring physiology. For the paternal age effect on TL to convey reliable information, it was predicted that the paternal age effect would exhibit a multi-generational character, providing integrated and thus more reliable information. This model leads to the prediction that grandfather’s age at the conception of the parent will be associated with longer TL in the grandchild.
Blood TLs (BTL) from young adults from Cebu, Philippines were measured. Consistent with previous findings, having an older father was associated with longer BTL (n=1,639, p<0.001). Consistent with our prediction, older paternal grandfathers had grandchildren with longer BTL (n=223, p=0.04). No such effect was found for maternal grandfathers (n=333, p=0.331). The effect sizes of the associations are large enough to be of biological importance.
These findings provide the first evidence that grandfather’s age at father’s conception influences grandchildren’s TL.
This work was supported by NSF and Wenner Gren Foundation grants. DTAE is supported by a NSF GRF. DNA extracts generously provided by Karen Mohlke.