A new study sheds light on the theory that aging is associated with the shortening of chromosomes in non-reproductive cells. Research results suggest the gene responsible for shortening the ends of chromosomes is inherited via the X chromosome.
Investigators measured the length of the end of the chromosomes, known as telomeres, in white blood cell DNA taken from a random sample of families living in northern Belgium. Telomere length was found to be similar between fathers and daughters, mothers and sons, mothers and daughters, and among siblings. However, the length was not different between fathers and sons and between spouses. Thus, the inheritance of a parental X chromosome (from mothers to sons and from both parents to daughters) was strongly correlated with similar telomere length between parents and children. Results also confirm telomere length is longer in women than in men.
Previous studies show the relative length of telomeres is associated with age-related illness and death. In one earlier study, telomere length was shorter in patients with atherosclerotic heart disease than in age-matched healthy patients. Clinical markers of aging, such as pulse pressure and survival, have also been associated with telomere length.
However researchers say more research needs to be done on the newly discovered X-linked inheritance and the hypothesis that genetic predisposition to chronic age-related disease may be associated with shortened telomeres.