A risk factor for stroke is the C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene. Studies have report a higher C677T homozygosity frequency in Chinese than in Europeans. Usually, the detection of genetic diseases is rather complicated on a large scale owing to the invasive sampling and a cumbersome DNA extraction process.
In a study by Dr. Li Yi and team from Peking University Shenzhen Hospital in China, DNA from stroke patients and healthy controls was extracted from the saliva using a magnetic nanoparticles-based method and from the blood using conventional methods. Real-time PCR results revealed that the C677T polymorphism was genotyped by PCR using DNA extracted from both saliva and blood samples. The genotype results were confirmed by gene sequencing, and results for saliva and blood samples were consistent. Therefore, this noninvasive magnetic nanoparticles-based method using saliva samples could be used to screen for the MTHFR C677T polymorphism in target populations. This study was published in the Neural Regeneration Research (Vol. 8, No. 32, 2013).