Which banding technique should be used if the addition of nonhomologous material to the q-arm of chromosome 16 is suspected?

When the addition of nonhomologous material to the q-arm of chromosome 16 is suspected, C-banding is the appropriate technique to use due to its ability to highlight specific regions of chromosomes. C-banding specifically targets the heterochromatic regions of chromosomes, particularly the centromeric areas and some terminal regions, allowing for the identification of additional chromatin material that may have been incorporated into a chromosome.

This technique would be beneficial in cases where structural abnormalities are suspected, as it can reveal insights about the presence of extra genetic material that is not normally seen in a standard karyotype. In contrast, other techniques like G-banding generally provide a more extensive view of the entire chromosomal structure and are more useful for examining banding patterns for the entire chromosome rather than specifically targeting the heterochromatic regions. Q-banding focuses on detecting specific patterns in the q-arm, while FISH (Fluorescence In Situ Hybridization) applies probes to visualize specific DNA sequences, which might not be necessary unless a more detailed investigation of specific genes is required.

Using C-banding allows the technologist to ascertain whether there has been an anomalous addition of genetic material in a focused and reliable way.