Diagnosing Genetic Disease And Carcinoma With Cell-free Plasma DNA

Part one:Diagnosing colorectal cancer by detecting the aberrant methylation of TPEF gene in plasmaObjective: To explore the feasibility of diagnosing colorectal cancer early and non-invasively, we analysed the methylation status of TPEF gene in Chinese patients and set up a method for detecting TPEF aberrant methylation in plasma. Methods: DNA was isolated from tissues and plasma, and the methylation status of TPEF gene was detected by methylation-specific PCR.Results: Aberrant methylation of TPEF gene was observed in 75.0% of the 32 tissue samples obtained from colorectal cancer patients and in 68.8% (22 of 32) of the paired plasma samples.Conclusion: Aberrant methylation of TPEF gene is a frequent event in Chinese colorectal cancer patients. It may be a useful biomarker for early diagnosis of colorectal cancer.Part two: Prenatal fetal sex diagnosis by detecting the fetal DNA in maternal plasmaObjective: To set up a reliable non-invasive method for fetal sex determination. Methods: There is a 6bp difference in the X-Y homologous region of amelogenin gene intron 3, maternal plasma DNA was amplified, then distinguishing the 6bp...