Method to remove human DNA when sequencing for parasite infection

A major challenge to sequencing eukaryotic parasites present in clinical samples is the abundance of ‘contaminating’ human DNA in samples. CDC has developed a method to reduce host DNA from biological samples prior to sequencing of the 18s gene, a universal gene which allows scientists to detect any parasitic organism by one DNA test.

Use of this technology will allow for 18s sequencing of parasites found in biological samples for pathogen identification, surveillance, and detection of new parasite pathogens. This technique could decrease the time required to diagnose infections in patients. Initial test results showed that samples not treated with restriction enzymes retain >95% human DNA, while treated samples yield five to ten fold increase in parasite DNA and one to two fold reduction in human DNA, allowing far greater capacity to detect parasite DNA in these treated samples. Thus far, this method was validated using 16 human blood-borne parasite species and was effective in detecting both single and mixed parasite infections.