Overview of contributors to TC. TL reflects the physical length of telomeric DNA repeats at the natural ends of chromosomes, which can be measured using methods such as TRF, flow-FISH, STELA, and long-read WGS. TC measures the total amount of telomeric DNA repeats and may include sources such as intrachromosomal telomeric insertions and neotelomeres formed at double-strand break sites. TC can be measured by methods like (qPCR), short-read WGS, and long-read WGS. Flow-FISH, flow cytometry–based fluorescence in situ hybridization; qPCR, quantitative polymerase chain reaction; STELA, single telomere length analysis; TRF, telomere restriction fragment. Figure created with BioRender. Tiong IS. (2025) https://BioRender.com/yg8q9ug.