Q&A column
Q. Is the evaluation of gene copies by RT-PCR or multiplex ligation-dependent probe amplification a qualitative or quantitative assay? Copy number analysis of genes or chromosomes determines a numerical value, with a normal autosomal count being two. However, an FDA-approved microarray test (CytoScan Dx assay, Thermo Fisher Scientific) is labeled as a qualitative assay for the detection of copy number variations. Read answer.
Q. How does using sodium heparin, in an attempt to reduce EDTA-induced platelet clumps, affect the platelet count? Read answer.
Q. How do you know whether thyroid-stimulating hormone isoforms have been measured in an assay when the TSH levels are very high and free T4 is considerably less than the reference interval (i.e. less than 50 percent of the reference interval)? Read answer.