Which of the following technologies is NOT commonly used in genomics?

Electrophoresis is primarily a technique used for separating macromolecules like DNA, RNA, and proteins based on size and charge. While it is an essential method in molecular biology for analyzing the results of techniques like PCR or assessing the output of sequencing, it is not a method that actively performs genomic sequencing or analysis in the way that next-generation sequencing, PCR, or microarrays do.

Next-generation sequencing is a high-throughput method that allows for rapid sequencing of large amounts of DNA, which is foundational in genomics for understanding genetic material at a deeper level. Polymerase chain reaction amplifies specific DNA sequences, making them more accessible for sequencing and analysis. Microarrays facilitate the examination of gene expression or genotyping multiple regions of a genome simultaneously.

Understanding these distinctions highlights the role of electrophoresis as a supporting technique rather than a primary technology used in genomics, making it the correct answer in this context.