Increasingly, saliva is emerging as an alternative to blood for DNA sampling for genomic studies.
The comfort in the collection of the sample in a non-invasive way, is a point in its favor facing the patient. On the other hand, its stability at room temperature facilitates both the storage and the transport of the samples against the complex logistics that blood samples require due to the need to maintain the cold chain.
The most controversial part seemed to be in the quantity and quality of the DNA obtained by the two types of samples. However, with the appropriate collection methods, the yield and quality of the results obtained by both routes are perfectly comparable.
In this post we bring you 3 key points that show the equivalence between using saliva or blood samples for genomic studies.
WHY ARE SALIVA OR BLOOD SAMPLES COMPARABLE FOR GENOMIC STUDIES?
1.- WORK FLOW IN THE LABORATORY
The laboratory workflow and extraction protocols are very similar whether starting with blood or saliva samples. Of course, in the second case, it is essential to have taken the sample with the appropriate kits, which allow collecting a liquid sample that will be processed in a very similar way to blood.
2.- DNA QUALITY
The DNA that is obtained from saliva samples comes mainly from the white blood cells present in it, so the DNA source is basically identical in both cases. This ensures that high-quality DNA is obtained.
3.- GENOMIC ANALYSIS APPLICATIONS
Today, the use of saliva samples is validated like blood for most technologies including PCR, arrays and sequencing, since the DNA yield obtained from saliva or blood samples for genomic studies it is equivalent in both cases (more info in this study).