Article

Assessment of the quality and quantity of genomic DNA recovered from canine blood samples by three different extraction methods.

Musculoskeletal Research Group, c/o Department of Veterinary Pathology, Faculty of Veterinary Science, University of Liverpool, Liverpool L69 3BX, UK.
Research in Veterinary Science (impact factor: 1.65). 09/2008; 85(1):74-9. DOI:10.1016/j.rvsc.2007.09.009 pp.74-9
Source: PubMed

ABSTRACT The ideal method for genomic DNA (gDNA) extraction should recover high quantities of pure, integral gDNA from the original sample source with minimal co-extraction of inhibitors of downstream processes. Canine ethylenediamine tetra-acetic acid (EDTA) treated and clotted blood samples were extracted by three different methods (a silica column method, a phenol-chloroform method and a modified salt precipitation method). Phenol-chloroform and modified salt precipitation based extractions demonstrated similar relative recovery of gDNA with EDTA preserved blood, but were less efficient at recovering gDNA from clotted blood. Spectrophotometer measurement of phenol-chloroform based extractions tended to overestimate the quantity of gDNA recovered from extractions, and was associated with the greater co-extraction of PCR inhibitors. The silica column method recovered gDNA with equal efficiency, purity and integrity irrespective of the sample type or method of quantification.

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Keywords

Canine ethylenediamine tetra-acetic acid
 
clotted blood
 
clotted blood samples
 
different methods
 
equal efficiency
 
gDNA
 
genomic DNA
 
greater co-extraction
 
inhibitors
 
integral gDNA
 
minimal co-extraction
 
modified salt precipitation method
 
original sample source
 
PCR inhibitors
 
phenol-chloroform method
 
salt precipitation
 
sample type
 
silica column method
 
similar relative recovery
 
Spectrophotometer measurement