TY - JOUR
T1 - Telomere length varies by DNA extraction method
T2 - Implications for epidemiologic research
AU - Cunningham, Julie M.
AU - Johnson, Ruth A.
AU - Litzelman, Kristin
AU - Skinner, Halcyon G.
AU - Seo, Songwon
AU - Engelman, Corinne D.
AU - Vanderboom, Russell J.
AU - Kimmel, Grace W.
AU - Gangnon, Ronald E.
AU - Riegert-Johnson, Douglas L.
AU - Baron, John A.
AU - Potter, John D.
AU - Haile, Robert
AU - Buchanan, Daniel D.
AU - Jenkins, Mark A.
AU - Rider, David N.
AU - Thibodeau, Stephen N.
AU - Petersen, Gloria M.
AU - Boardman, Lisa A.
PY - 2013/11
Y1 - 2013/11
N2 - Background: Both shorter and longer telomeres in peripheral blood leukocyte (PBL) DNA have been associated with cancer risk. However, associations remain inconsistent across studies of the same cancer type. This study compares DNA preparation methods to determine telomere length from patients with colorectal cancer. Methods: We examined PBL relative telomere length (RTL) measured by quantitative PCR (qPCR) in 1,033 patients with colorectal cancer and 2,952 healthy controls. DNA was extracted with phenol/chloroform, PureGene, or QIAamp. Results: We observed differences in RTL depending on DNA extraction method (P < 0.001). Phenol/chloroform-extracted DNA had a mean RTL (T/S ratio) of 0.78 (range 0.01-6.54) compared with PureGeneextracted DNA (mean RTL of 0.75; range 0.00-12.33). DNA extracted by QIAamp yielded a mean RTL of 0.38 (range 0.02-3.69).Wesubsequently compared RTL measured by qPCR from an independent set of 20 colorectal cancer cases and 24 normal controls in PBLDNAextracted by each of the three extraction methods. The range of RTL measured by qPCR from QIAamp-extracted DNA (0.17-0.58) was less than from either PureGene or phenol/chloroform (ranges, 0.04-2.67 and 0.32-2.81, respectively). Conclusions: RTL measured by qPCR from QIAamp-extracted DNA was less than from either PureGene or phenol/chloroform (P < 0.001). Impact: Differences in DNA extraction method may contribute to the discrepancies between studies seeking to find an association between the risk of cancer or other diseases and RTL.
AB - Background: Both shorter and longer telomeres in peripheral blood leukocyte (PBL) DNA have been associated with cancer risk. However, associations remain inconsistent across studies of the same cancer type. This study compares DNA preparation methods to determine telomere length from patients with colorectal cancer. Methods: We examined PBL relative telomere length (RTL) measured by quantitative PCR (qPCR) in 1,033 patients with colorectal cancer and 2,952 healthy controls. DNA was extracted with phenol/chloroform, PureGene, or QIAamp. Results: We observed differences in RTL depending on DNA extraction method (P < 0.001). Phenol/chloroform-extracted DNA had a mean RTL (T/S ratio) of 0.78 (range 0.01-6.54) compared with PureGeneextracted DNA (mean RTL of 0.75; range 0.00-12.33). DNA extracted by QIAamp yielded a mean RTL of 0.38 (range 0.02-3.69).Wesubsequently compared RTL measured by qPCR from an independent set of 20 colorectal cancer cases and 24 normal controls in PBLDNAextracted by each of the three extraction methods. The range of RTL measured by qPCR from QIAamp-extracted DNA (0.17-0.58) was less than from either PureGene or phenol/chloroform (ranges, 0.04-2.67 and 0.32-2.81, respectively). Conclusions: RTL measured by qPCR from QIAamp-extracted DNA was less than from either PureGene or phenol/chloroform (P < 0.001). Impact: Differences in DNA extraction method may contribute to the discrepancies between studies seeking to find an association between the risk of cancer or other diseases and RTL.
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U2 - 10.1158/1055-9965.EPI-13-0409
DO - 10.1158/1055-9965.EPI-13-0409
M3 - Article
C2 - 24019396
AN - SCOPUS:84887300926
SN - 1055-9965
VL - 22
SP - 2047
EP - 2054
JO - Cancer Epidemiology Biomarkers and Prevention
JF - Cancer Epidemiology Biomarkers and Prevention
IS - 11
ER -