28,000 PATIENTS
The pattern of associations the researchers discovered suggest today’s population retains Neanderthal DNA that may have provided modern humans with adaptive advantages 40,000 years ago as they migrated into new non-African environments with different pathogens and levels of sun exposure. However, many of these traits may no longer be advantageous in modern environments.
One example of this is a Neanderthal variant that increases blood coagulation. It could have helped our ancestors cope with new pathogens encountered in new environments by sealing wounds more quickly and preventing pathogens from entering the body. In modern environments this variant has become detrimental, because hypercoagulation increases risk for stroke, pulmonary embolism, and pregnancy complications.
To discover these associations, the researchers used a database containing 28,000 patients whose biological samples have been linked to anonymized versions of their electronic health records. The data came from eMERGE—the Electronic Medical Records and Genomics Network funded by the National Human Genome Research Institute—which links digitized records from Vanderbilt University Medical Center’s BioVU databank and eight other hospitals around the country.
This data allowed the researchers to determine if each individual had ever been treated for a specific set of medical conditions, such as heart disease, arthritis, or depression. Next they analyzed the genomes of each individual to identify the unique set of Neanderthal DNA that each person carried. By comparing the two sets of data, they could test whether each bit of Neanderthal DNA individually and in aggregate influences risk for the traits derived from the medical records.
“Vanderbilt’s BioVU and the network of similar databanks from hospitals across the country were built to enable discoveries about the genetic basis of disease,” Capra says. “We realized that we could use them to answer important questions about human evolution.”
The work establishes a new way to investigate questions about the effects of events in recent human evolution. The current study was limited to associating Neanderthal DNA variants with physical traits (phenotypes) included in hospital billing codes, but there is a lot of other information contained in the medical records, such as lab tests, doctors’ notes, and medical images, that Capra is working on analyzing in a similar fashion.
Republished from Futurity.org as a derivative work under the Attribution 4.0 International license. Original article posted to Futurity by David Salisbury-VU.
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