* Genetic Mapping: They used family studies to track the inheritance of diabetes and linkage analysis to identify regions of chromosomes associated with the disease. This narrowed down the search to a specific area on chromosome 11.
* DNA Sequencing: Once the approximate location was known, they sequenced the DNA in that region. This allowed them to identify the specific gene responsible for insulin production.
* Cloning and Expression: They cloned the gene and inserted it into other cells (like bacteria) to produce insulin. This allowed them to study the gene's function and create a reliable source of insulin for treatment.
In summary: It was a process of localization, identification, and validation of the insulin gene, employing various techniques from different fields of genetics and molecular biology.
