title: The relative lengths of individual telomeres are defined in the zygote and strictly maintained during life.
abstract: Previous studies have indicated that average telomere length is partly inherited (Slagboom et al., 1994; Rufer et al., 1999) and that there is an inherited telomere pattern in each cell (Graakjaer et al., 2003); (Londoño-Vallejo et al., 2001). In this study, we quantify the importance of the initially inherited telomere lengths within cells, in relation to other factors that influence telomere length during life. We have estimated the inheritance by measuring telomere length in monozygotic (MZ) twins using Q-FISH with a telomere specific peptide nucleic acid (PNA)-probe. Homologous chromosomes were identified using subtelomeric polymorphic markers. We found that identical homologous telomeres from two aged MZ twins show significantly less differences in relative telomere length than when comparing the two homologues within one individual. This result means that towards the end of life, individual telomeres retain the characteristic relative length they had at the outset of life and that any length alteration during the lifespan impacts equally on genetically identical homologues. As the result applies across independent individuals, we conclude that, at least in lymphocytes, epigenetic/environmental effects on relative telomere length are relatively minor during life.
authors.affiliation: Institute for Human Genetics, University of Aarhus, Aarhus, Denmark.
authors.forename: Jesper
authors.initials: J
authors.lastname: Graakjaer
authors.forename: Leigh
authors.initials: L
authors.lastname: Pascoe
authors.forename: Héra
authors.initials: H
authors.lastname: Der-Sarkissian
authors.forename: Gilles
authors.initials: G
authors.lastname: Thomas
authors.forename: Steen
authors.initials: S
authors.lastname: Kolvraa
authors.forename: Kaare
authors.initials: K
authors.lastname: Christensen
authors.forename: José-Arturo
authors.initials: JA
authors.lastname: Londoño-Vallejo
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D017403:In Situ Hybridization; D008214:Lymphocytes / Q000378:metabolism; D008954:Models, Biological; D016615:Telomere / Q000378:metabolism*; D018433:Twin Studies as Topic; D015053:Zygote / Q000378:metabolism*