Practice question

Interphase FISH uses decondensed nuclear chromatin, where spatial resolution and signal coalescence are suboptimal. Tandem repeat clusters, being repetitive and often closely spaced, produce merged or diffuse fluorescent signals that are hard to quantitate and enumerate in interphase nuclei. Metaphase chromosomes provide condensed, linearly ordered targets where repeat arrays are linearly resolved. Microarray and SAGE interrogate sequence content differently. Hence, interphase FISH suffers reduced sensitivity and specificity for enumerating tandem repeats compared to metaphase FISH, which offers superior cytogenetic resolution of repeated sequences and breakpoints.