Genomics Core Facility (GCF)

RNA/DNA sample preparation and QC

Important to know about RNA/DNA Sample Preparation and Quality Control


It is important that users provide DNA or RNA samples with required quality and quantity.

Here are some general guidelines for sample preparation and quality control:


RNA quality check

RNA samples should be free of proteins, DNA, phenol, ethanol and salt.

We recommend RNeasy kit from Qiagen or similar for RNA preparation. If TRIzol based methods are used to extract RNA from tissues, we recommend a cleanup procedure with Qiagen RNeasy mini kit following the phenol extraction.


If possible, DNase treatment should always be performed when extracting RNA for genomic analysis. 


RNA quantitation

We recommend NanoDrop or Qubit® fluorometric quantitation. 


RNA quality assessment

The quality of total RNA samples is the most important factor in RNA-Seq. RNA samples should be quality checked on a bioanalyzer (or similar system). If there is significant degradation (when RNA Integrity Number, or RIN, is below 7.0), we will request the customer to re-submit total RNA samples of satisfactory quality.


DNA quantitation

We recommend the Qubit® fluorometric quantitation for quick and accurate quantitation. You can also check the OD260/280 ratio using a NanoDrop, this ratio is a indicator of purity and should be between 1.8 -2.0 for a good DNA sample. 


Genomic DNA Quality Assessment

DNA samples must not be highly degraded. We recommend quality check on a Bioanalyzer or a 1 % agarose gel. High quality genomic DNA should give a major band of 10-20 kb on the gel.