NEW YORK (GenomeWeb) – An ancient DNA analysis suggests that a 17th century mummy showing signs of atherosclerotic cardiovascular disease (ASCVD) carried risky versions of variants implicated in the condition in present-day populations.
Researchers from Seoul National University and the University of Ulsan used PCR and targeted sequencing to assess patterns at 10 ASCVD-related variants in a female mummy from Korea, dubbed the Joseon mummy for the tomb where she was found. Their results, appearing online yesterday in PLOS One, pointed to the presence of more than half-a-dozen heart disease-associated variants in the mummy genome.
"We were able to establish that the 17th century Korean female had a strong genetic predisposition to increased risk of ASCVD," senior author Eunju Lee, a researcher at the University of Ulsan's Asan Medical Center, and his co-authors wrote. "The current paleogenetic diagnosis, the first of its kind outside Europe, re-confirms its utility as an adjunct modality for confirmatory diagnosis of ancient ASCVD."
The female mummy, buried in a coffin made from wood traced back to the 1560s, was found in a tomb in Korea's Mungyeong county in 2010, the researchers explained. Analyses done using computed tomography imaging and other approaches uncovered arterial wall plaques, hemorrhages, and additional features in the mummy that appeared to be consistent with ASCVD.
"Although the resulting report was a rare and invaluable conjecture on the disease status of an ancient East Asian population, the diagnosis had been based only on anatomical and radiological techniques," the authors wrote, "and so could not confirm the existence of ASCVD in the mummy."
Using PCR-based cloning and targeted Sanger sequencing, the team sought genetic support for the diagnosis, focusing on patterns at 10 SNPs associated with atherosclerosis, coronary artery disease, and/or myocardial infarction in prior studies done in populations from South Asia and Europe, in general, or from South Korea, Japan, or China, specifically.
The researchers reported seeing seven SNP alleles that have been implicated in ASCVD in populations from East Asia or across multiple populations — findings they went on to verify with a ThermoFisher Applied Biosystems SNaPshot multiplex kit.
The team also analyzed mitochondrial haplotypes in the proposed mummy samples and in samples from those carrying out the analyses to make sure modern DNA had not made its way into the samples and muddied the heart disease variant results.
"It is common to think that ASCVD is of concern only for modern people with their various risk factors including hypertension, diabetes, smoking, high caloric diet, and hyperlipidemia," the authors noted. "However, genetic factors must not be ignored either, as many [coronary artery disease] and atherosclerosis cases have been correlated with the genetic predisposition of the patient."