A salting out and resin procedure for extracting Schistosoma mansoni DNA from human urine samples

Martin J Enk,Nilton B Rodrigues,Guilherme Oliveira E Silva

doi:10.1186/1756-0500-3-115

Martin J Enk, Nilton B Rodrigues + Show 1 more

Open Access

https://doi.org/10.1186/1756-0500-3-115

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Abstract

BackgroundIn this paper a simple and cheap salting out and resin (InstaGene matrix® resin - BioRad) DNA extraction method from urine for PCR assays is introduced. The DNA of the fluke Schistosoma mansoni was chosen as the target since schistosomiasis lacks a suitable diagnostic tool which is sensitive enough to detect low worm burden. It is well known that the PCR technique provides high sensitivity and specificity in detecting parasite DNA. Therefore it is of paramount importance to take advantage of its excellent performance by providing a simple to handle and reliable DNA extraction procedure, which permits the diagnosis of the disease in easily obtainable urine samples.FindingsThe description of the extraction procedure is given. This extraction procedure was tested for reproducibility and efficiency in artificially contaminated human urine samples. The reproducibility reached 100%, showing positive results in 5 assay repetitions of 5 tested samples each containing 20 ng DNA/5 ml. The efficiency of the extraction procedure was also evaluated in a serial dilution of the original 20 ng DNA/5 ml sample. Detectable DNA was extracted when it was at a concentration of 1.28 pg DNA/mL, revealing the high efficiency of this procedure.ConclusionsThis methodology represents a promising tool for schistosomiasis diagnosis utilizing a bio-molecular technique in urine samples which is now ready to be tested under field conditions and may be applicable to the diagnosis of other parasitic diseases.

Highlights

This methodology represents a promising tool for schistosomiasis diagnosis utilizing a bio-molecular technique in urine samples which is ready to be tested under field conditions and may be applicable to the diagnosis of other parasitic diseases
Schistosomiasis caused by Schistosoma mansoni is a major public health problem in countries of Latin America, the Caribbean and Africa [1,2]
The results from the 1st sample set show the high reproducibility of the DNA extraction method, and those from the 2nd confirm the test's efficiency by detecting 1.28 pg DNA/mL urine, an approximately 3,000 times smaller quantity of DNA than in the first dilution

Summary

Introduction

Schistosomiasis caused by Schistosoma mansoni is a major public health problem in countries of Latin America, the Caribbean and Africa [1,2]. Conclusions: This methodology represents a promising tool for schistosomiasis diagnosis utilizing a bio-molecular technique in urine samples which is ready to be tested under field conditions and may be applicable to the diagnosis of other parasitic diseases.

Results

Conclusion