Comparing DNA quantity and quality using saliva collection following food and beverage consumption

With the democratization of genetic testing, researchers, clinicians, and educators must consider the varying degree of field conditions when collecting samples for genetic analyses. For genotyping or sequencing studies, study designers have multiple options from which to choose, including cheek swabs and saliva sampling. One significant benefit of saliva collection is that it can be done remotely, in the privacy of one's home. This same benefit adds a risk of compliance. Therefore, our goal with this study was to see if the quality and quantity of the saliva collection by a saliva DNA collection kit would be affected by not following the manufacturer's directions, i.e., drinking or eating right before collection.

We asked five participants to collect saliva samples according to the manufacturer's guidance and also after consuming five food items or beverages. We evaluated DNA quantity and quality post-purification using spectroscopy, electrophoresis, and polymerase chain reaction genotyping. Consistent with our hypothesis, we did not see a difference in quantity or quality of the isolated DNA. From our results, we conclude that the manufacturer's instructions serve as an ideal guideline, but the collection devices are robust enough to permit flexibility in sampling at home or in the field.