University of Pittsburgh Cancer Institute 1 article published in JoVE Cancer Research Modified Terminal Restriction Fragment Analysis for Quantifying Telomere Length Using In-gel Hybridization Frank J. Jenkins1,2, Charles M. Kerr2, Elise Fouquerel2,3, Dana H. Bovbjerg2,4, Patricia L. Opresko2,3 1Departments of Pathology and Infectious Diseases and Microbiology, University of Pittsburgh, 2University of Pittsburgh Cancer Institute, 3Department of Environmental and Occupational Health, University of Pittsburgh, 4Departments of Psychiatry, Psychology, Behavioral & Community Health Sciences, University of Pittsburgh In this article, a detailed protocol for quantifying telomere length using a modified terminal restriction fragment analysis is discussed that provides fast and efficient direct measurement of telomere length. This technique can be applied to a variety of cell sources of DNA for quantifying telomere length.