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Gigabase (Gb)

updated: April 16, 2024


A gigabase (abbreviated Gb) is a unit of measurement used to help designate the length of DNA. One gigabase is equal to 1 billion bases.



Gigabase. When I think of gigabase, it makes me think of another similar word that we hear a lot today, gigabytes. Most of these units refer to the size of information that can be stored. Modern computers and smart phones have memory chips that store gigabytes of information. That's how much we need to store our memories and pictures, e-mails, apps, contacts. This analogy can help us appreciate the size of human genome, about 3.4 gigabases. Human genome stores a lot of information to help our body function the way it does.

Oleg Shchelochkov
Oleg A. Shchelochkov, M.D.


Medical Genetics and Genomic Medicine Training Program