An international team of scientists has mapped the genetic makeup of 47 strains of bacteria known to cause Lyme disease. This research aims to improve diagnostic tests and targeted treatments for Borrelia burgdorferi, the primary cause of Lyme disease, which is prevalent in the United States and Europe. The findings were published in the journal mBio.
Lyme disease affects nearly 500,000 people annually in the United States alone. If untreated, it can lead to severe complications affecting joints, the heart, and the nervous system. Researchers warn that climate change and other environmental factors may increase global cases of Lyme disease. Some Borrelia species sequenced in this study could serve as a genetic reservoir for future evolution.
"This is a seminal study with not only new genetic findings that map out the genomes of 47 strains of Borrelia; it is a body of work that provides researchers with data and tools going forward to better tailor treatment against all causes of Lyme disease," said Benjamin Luft, MD, Professor at Stony Brook University’s Renaissance School of Medicine.
The research involved investigators from over a dozen institutions worldwide who sequenced complete genomes representing all 23-known species in the group. Many had not been sequenced before. This included multiple strains commonly associated with human infections and species not previously known to cause human diseases.
By comparing these genomes, researchers traced the evolutionary history of Lyme disease bacteria back millions of years. They found that these bacteria likely originated before Pangea's breakup, explaining their global distribution.
The study also highlighted how these bacteria exchange genetic material within and between species through recombination. This process allows rapid evolution and adaptation to new environments. Specific hot spots where this genetic exchange occurs most frequently were identified, often involving genes aiding interaction with tick vectors and animal hosts.
"By understanding how these bacteria evolve and exchange genetic material, we’re better equipped to predict and respond to changes in their behavior," explained Weigang Qiu, PhD, Senior Author and Professor at City University of New York.
To support ongoing research, the team developed web-based software (BorreliaBase.org) enabling scientists to compare Borrelia genomes and identify determinants of human pathogenicity.
Future research will expand genome analysis to include more strains from understudied regions. The team will also investigate genes unique to disease-causing strains for potential therapeutic targets.
This research was primarily funded by the National Institute of Health’s National Institutes of Allergy and Infectious Diseases (NIAID) with additional support from the Steven & Alexandra Cohen Foundation.
Twenty authors contributed to this paper including Dr. Luft. Leading collaborators include Sherwood Casjens from University of Utah School of Medicine, Weigang Qiu from City University of New York, Steven Schutzer from Rutgers New Jersey Medical School, Claire Fraser and Emmanuel Mongodin from University of Maryland School of Medicine, and Richard G. Morgan from New England BioLabs.