Early detection of CRC and adenomas reduces CRC-related mortality. The optimal screening test for CRC is still a subject of debate, and molecular stool sample analysis could provide a valid alternative to conventional methods in terms of compliance and practicability. Seven fecal DNA storage systems were evaluated in two successive phases. In the first phase of the study was selected the preservative buffer able to ensure the best human DNA recovery. In the second phase was evaluated human DNA stability, amplificability and integrity in DNA extracted from selected buffer. Results showed that the best performance was obtained in samples stored in 100？mM EDTA buffer and Genefec buffer. Likewise buffer addition yielded a significant increase in DNA stability and integrity without PCR inhibition, compared to the matched aliquots with no buffer added. Our study shows that samples collected in stabilization solution stabilize DNA so that intact nucleic acids, are more effectively detectable in the molecular assay. DNA buffer preservation and storage conditions could be useful to guarantee the most consistent yield in human DNA. Stabilization buffer addition to stool samples prior to transport presents an easily implemented solution that appears to be highly effective. Overall DNA extracted from faeces preserved in preservative buffer can feasibility been used for molecular analysis leading to an increase of assay sensitivity. 1. Introduction Colorectal cancer (CRC) is one of the most common malignancies worldwide. CRC is the third leading cause of cancer-related mortality and the second leading cause of cancer-related incidence. Nevertheless, the survival rate of patients with CRC is high if this cancer can be diagnosed and surgically resected at an early stage [1]. Early detection of CRC reduces CRC-related mortality, and removal of its precursor lesions (adenomas) reduces both the incidents and mortality of CRC [2]. Thus, population screening of asymptomatic average risk persons is arguably the most effective intervention for preventing any cancer, and it has great potential to reduce morbidity and mortality [2–6]. Currently, several possible screening techniques are available and recommended by scientific societies: guaiac and immunochemical faecal occult blood test (FOBT), sigmoidoscopy, colonoscopy, computed tomography colonography (CT colonography or CTC), and faecal DNA test [7]. FOBT has been used widely as a screening test for CRC [1]. Randomized clinical trials demonstrated that screening with FOBT reduces mortality from CRC [3, 4]. Moreover, faecal
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