High-quality DNA purified from saliva collected with the Oragene DNA Self-Collection Kit using the Gentra Puregene Buccal Cell Kit

Laboratories performing DNA-based clinical tests or population genetics studies often prefer to use alternatives to invasive whole blood sample collection. One such alternative is the Oragene DNA Self-Collection Kit (DNA Genotek), which provides a convenient method for storing and shipping saliva samples at room temperature. It is important, however, that the DNA purified from this sample type is of high quality and performs well in sensitive downstream applications such as PCR. High-quality DNA can be purified from saliva collected with the Oragene DNA Self-Collection Kit using the Gentra Puregene Buccal Cell Kit.

Materials and methods

Saliva samples (2 ml) were collected from 16 individuals and mixed with 2 ml DNA-preserving solution in the Oragene DNA collection vial, according to the manufacturer's instructions.

The vials were incubated overnight in a 50°C air incubator and then stored at room temperature. DNA was purified from all samples using the Gentra Puregene Buccal Cell Kit. All DNA samples were hydrated in 300 µl DNA Hydration Solution.

DNA yield and purity were determined by measuring the absorbance at 260 nm (A₂₆₀) and the ratio of absorbance at 260 nm and 280 nm (A₂₆₀/A₂₈₀) with background correction. The quality of DNA was confirmed by running 100 ng hydrated DNA on a 0.7% agarose gel and by amplifying the CYP2D6 gene (1.5 kb) using 100 ng purified DNA in a final reaction volume of 50 µl. PCR efficiency was visualized by running a 10 µl aliquot from the PCR on a 1% agarose gel.

Results

The average total DNA yield from the Oragene DNA/saliva samples was 85.5 ± 47.3 µg, with an average DNA purity (A₂₆₀/A₂₈₀) of 1.79 ± 0.03.

High-molecular-weight DNA was purified from all samples, as visualized on agarose gels (see figure "High-quality DNA from Oragene DNA/saliva samples"). In addition, all purified DNA amplified successfully, indicating that the DNA was of high quality (see figure "Efficient amplification of Oragene DNA/saliva samples").

High-quality DNA from Oragene DNA/saliva samples. The quality of DNA purified from saliva collected with the Oragene DNA Self-Collection Kit using the Gentra Puregene Buccal Cell Kit was confirmed by running 100 ng hydrated DNA on a 0.7% agarose gel. M1: uncut Lambda DNA; M2: Lambda HindIII marker.

Efficient amplification of Oragene DNA/saliva samples. Amplification of the 1.5 kb CYP2D6 gene (50 µl reaction volume) was performed using 100 ng DNA purified from Oragene DNA/saliva samples. PCR products (10 µl) were visualized on a 1% agarose gel. M: 1 kb ladder.

Oragene•DNA

The Oragene®•DNA sample collection kit provides an all-in-one system for the collection, stabilization, transportation and purification of DNA from saliva.

All genetic research and testing starts with the collection of DNA samples. Blood samples are invasive to collect, as well as complex and costly to ship, store and process. Buccal swabs provide a low quality and quantity of DNA, typically resulting in failed samples and a requirement to recollect, incurring additional cost, effort and time.

Eliminate these challenges by collecting superior samples with the Oragene sample collection product line.

• Easy collection, transportation and processing
• Painless, non-invasive collection of high-quality, high-quantity DNA
• DNA is stable for years at room temperature
• Proven on downstream applications

Oragene•DNA is superior to blood

• Higher donor compliance with painless self-collection
• Lower collection costs with no phlebotomy required
• Safer handling
• Easier to purify

Oragene•DNA is superior to mouthwash & buccal swabs

• Higher DNA yield and quality
• More reliable for downstream applications
• Lowest bacterial content of all oral collection methods
• Less invasive and completely painless: Most mouthwash donor protocols require the patient to swish alcohol-based mouthwash for at least one minute