Moby Dick: Or, the imprecision of genetic testing

Moby Dick: Or, the imprecision of genetic testing
Image: Herman Melville/Library of Congress
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Understanding the scale of the human genome is no easy task. With the rise of at-home testing kits, it may feel like getting your DNA sequenced is straightforward. However, while technical improvements have made direct-to-consumer (DTC) testing easier than ever, the simplicity of the reports they provide belies the difficulties of accurate gene analysis.

Let’s consider how small genetic variation is with the use of a metaphor.

Imagine Herman Melville’s 1851 classic Moby Dick, as if it were the human genome. Our DNA is roughly six billion base pairs packed into 46 chromosomes. Published in 1851, this whaling epic is over 206,000 words in length and—if you read about 30 pages a day—it would take you about three weeks to complete.