Final answer:
Comparative genomics is the sequencing technique used to identify regions of similarity between different cell types or species, relying on sequence alignment to elucidate evolutionary relationships.
Step-by-step explanation:
The sequencing technique used to identify regions of similarity between cell types or species is comparative genomics. This field involves the comparison of genomes between different organisms. With the aim of understanding how these organisms are related to each other and how they have evolved, comparative genomics analyzes the structure and function of their genetic material. This process often entails sequence alignment of proteins, DNA, or RNA to find similar regions that may indicate shared ancestry or evolutionary conservation. Key methods in this field, such as PCR amplification and microarray analysis, play supportive roles in generating the necessary DNA quantities and examining gene expression patterns, respectively.