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Table 1 Variability of LINE-1 methylation levels of DNA from cryo-preserved tissue

From: Why do results conflict regarding the prognostic value of the methylation status in colon cancers? the role of the preservation method

converted DNA samples PCR 1 (% of methylation) PCR 2 (% of methylation) SD due to different PCR and different pyrosequencing  
  pyrosequencing 1 pyrosequencing 2 pyrosequencing 1 pyrosequencing 2     
  CpG site 1 CpG site 2 CpG site 3 CpG site 1 CpG site 2 CpG site 3 CpG site 1 CpG site 2 CpG site 3 CpG site 1 CpG site 2 CpG site 3 CpG site 1 CpG site 2 CpG site 3  
A1 55.9 62.9 62.3 55.0 62.1 62.2 56.5 61.6 59.3 54.6 63.4 61.4 0.9 0.8 1.4 mean = 0.9
A2 53.1 63.1 59.7 56.0 63.3 59.5 53.2 62.7 60.0 57.5 62.3 60.5 2.2 0.4 0.4  
A3 55.7 61.9 58.6 55.4 61.8 61.1 54.8 60.6 59.6 55.3 62.5 61.6 0.4 0.8 1.4  
A4 54.1 63.8 60.7 56.4 63.6 59.9 56.4 63.7 60.3 55.8 64.1 59.6 1.1 0.2 0.5  
B1 56.3 61.8 62.7 57.8 63.1 63.5 58.0 62.9 60.6 56.7 64.1 61.4 0.8 0.9 1.3  
B2 55.9 63.4 62.9 57.9 64.0 63.2 55.2 63.1 62.5 58.6 64.7 63.3 1.6 0.7 0.4  
bisulfite-to-bisulfite SD 1.3 0.8 1.8 1.2 0.9 1.7 1.7 1.1 1.1 1.5 0.9 1.2     
  mean = 1.3     
SD between all measures of site 1 1.4%
SD between all measures of site 2 1.0%
SD between all measures of site 3 1.4%
  1. The levels of methylation (%) of the three studied CpG sites are given according to the converted DNA sample analysed (A1 through B2) and for each condition of analysis (PCR and pyrosequencing). Numbers in bold italics indicate minimal values of methylation on all measures for each CpG site. Numbers in bold indicate maximal values of methylation on all measures for each CpG site