title: Measurement of telomere length: a new assay using QuantiGene chemistry on a Luminex platform.
abstract: BACKGROUND
  Telomeres are tandem repeats of sequences present at the end of the chromosomes that maintain chromosomal integrity. After repeated cell division, telomeres shorten to a critical level, triggering replicative senescence or apoptosis, which is a key determinant of cellular aging. Short telomeres also contribute to genome instability and are a hallmark of many cancers. There are several methods for estimating telomere length (TL) from extracted DNA samples. Southern blot is accurate but requires a large quantity of DNA and is expensive. qPCR is cost-effective and requires a small quantity of DNA and is therefore widely used for large-scale epidemiologic studies; however, it typically requires triplicates. We describe a novel multiplexed probe-based non-PCR method for TL measurement.
  
  
  METHODS
  A small amount of DNA (∼50 ng) is hybridized to telomere repeat sequence-specific probes (T) and a reference single gene probes (R). T and R signals are detected from a single reaction well containing the same input DNA. Branching DNA technology is used to amplify the signal, which is detected by Luminex technology.
  
  
  RESULTS
  The intra- and interassay CV (∼3% and ∼5%, respectively) shows the precision of the new assay and the measurements from single well correlated well with traditional single-plex qPCR run in triplicate (r = 0.7 to 0.8). The assay was also validated in an independent set of samples using Southern blot (r = 0.74).
  
  
  CONCLUSIONS
  We describe a novel assay for TL assessment using the Luminex platform.
  
  
  CONCLUSIONS
  This may offer an alternative cost-efficient way to study TL in extracted DNA samples. See all the articles in this CEBP Focus section, "Biomarkers, Biospecimens, and New Technologies in Molecular Epidemiology."
authors.affiliation: Department of Health Studies, Biological Sciences Division, the University of Chicago, Chicago, Illinois. kibriya@uchicago.edu.
authors.forename: Muhammad G
authors.initials: MG
authors.lastname: Kibriya
authors.affiliation: Department of Health Studies, Biological Sciences Division, the University of Chicago, Chicago, Illinois.
authors.forename: Farzana
authors.initials: F
authors.lastname: Jasmine
authors.affiliation: Department of Health Studies, Biological Sciences Division, the University of Chicago, Chicago, Illinois.
authors.forename: Shantanu
authors.initials: S
authors.lastname: Roy
authors.affiliation: Department of Health Studies, Biological Sciences Division, the University of Chicago, Chicago, Illinois. Department of Human Genetics, the University of Chicago, Chicago, Illinois. Department of Medicine, the University of Chicago, Chicago, Illinois. Comprehensive Cancer Center, the University of Chicago, Chicago, Illinois.
authors.forename: Habibul
authors.initials: H
authors.lastname: Ahsan
authors.affiliation: Department of Health Studies, Biological Sciences Division, the University of Chicago, Chicago, Illinois. Comprehensive Cancer Center, the University of Chicago, Chicago, Illinois.
authors.forename: Brandon
authors.initials: B
authors.lastname: Pierce
mesh_terms: D001681:Biological Assay; D015139:Blotting, Southern / Q000379:methods*; D004247:DNA / Q000235:genetics*; D006801:Humans; D016615:Telomere / Q000737:chemistry*; D059506:Telomere Shortening / Q000502:physiology*
chemical_list: D004247:DNA