The editors of Science Translational Medicine this week published an expression of concern regarding a paper published in the journal earlier this year that described the use of circulating tumor DNA (ctDNA) methylation profiles to diagnose colorectal cancer and predict disease progression. In the paper, a led by Sun-Yat Sen University Cancer Center-led research team reported that a ctDNA methylation marker called cg10673833 could detect colorectal cancer and precancerous lesions in a high-risk population with high sensitivity and specificity. The journal's editors state, however, that the methylation status at cg10673833 could not have been measured using the assay cited in the paper because it exclusively detects methylation at cg05575921. While the scientists have since provided a different description of their methods, it remains unclear why the erroneous information about the assay was presented in the original paper, the editors write.
A portable point-of-care DNA testing platform with potential applications in clinical diagnostics, food safety, agricultural protection, and environmental monitoring is described in Science Advances this week. Developed by a team led by Third Military Medical University scientists, the platform — called POCKET, short for point-of-care kit for the entire test — is less than 100 grams and smaller than 25 centimeters in length. It consists of a chip containing a 3D-printed sample preparation unit and a microfluidic signal amplification unit; and a foldable detection box that uses a smartphone as a heater, an incubator, a detector, and a result reader. The investigators use POCKET to detect various types of DNA from clinical blood and buccal samples, pathogen-specific DNA sequences from urine samples, and bacterial DNA in milk, river water, and on plant leaves. The Scan and 360Dx have more on this, here and here.