How do you measure telomere length?

Telomere length can be measured using several methods, including quantitative PCR (qPCR), Southern blotting, fluorescence in situ hybridization (FISH), and flow cytometry. qPCR measures the relative abundance of telomeric DNA, while Southern blotting is a more traditional technique that detects telomere length by using specific probes. FISH allows for the visualization of telomeres directly in cells, and flow cytometry can be used in combination with FISH to analyze telomere length in a population of cells. Each method varies in precision and sensitivity.