Q5. How stable is the DNA and how should it be stored? ECACC recommends that cDNA is stored at -80 o C when not in use; repeat thawing should be avoided so we recommend making smaller aliquots of the cDNA after the first thaw. Some laboratories have reported storing cDNA at -20 o C and +4 o C for extended periods (1-2 months) however there is no stability data for these temperatures currently available.