DNA from tissues of young mice is optimal for genotyping|
Picazo, María G. & García-Olmo, Dolores C.
Background: Genotyping of mice is a common procedure in animal facilities. The aim of this study was to compare
the quantity and quality of DNA extracted from samples obtained from young mice (YM; 10 d old) and adult mice
(AM; 12 weeks old).We collected samples from the tail and ear of YM and AM. We also sampled blood, check
cells (via buccal swabs), hair and fecal pellets of AM, and biopsied distal phalanx of YM. We isolated DNA
using commercial kits and determined concentrations and purity by spectrophotometry. The integrity of DNA
was evaluated by agarose-gel electrophoresis and polymerase chain reaction (PCR).
Results: DNA in all samples was amplified successfully but the intensities of bands after electrophoresis was
heterogeneous. In general, tissues from YM yielded more DNA than those from AM, with differences being
statistically significant for ear samples (38 ± 12 ng/μL for YM; 7 ± 3 ng/μL for AM; P = 0.006). In YM, the
most DNA was obtained from ear and tail samples, with differences from the amounts obtained from phalanx
samples being statistically significant (P = 0.02 and P = 0.005, respectively). In AM, the most DNA was
obtained from tail and blood samples. Samples obtained by non-invasive sampling methods in adults resulted
in a deficient DNA extraction.
Conclusions: The results of the present study do not support the previous recommendations for using
non-invasive methods to genotype adult animals. The use of newborn tissue samples showed the highest
efficiency for DNA extraction.
DNA extraction; Genotyping; Mouse