Table 2

Data used to determine the detection and quantification limits of the rtqPCR method for the amplification of the wt soybean sequence

Dilution level^a

1

2

3

4

5

6

7

Expected wt DNA content (%)

5.00

1.00

0.20

0.04

0.0080

0.0016

0.0008

Estimated wt genome copies (n.)

8,889

1778

356

71

14.2

2.8

0.6

Signal rate^b

9/9

9/9

9/9

9/9

9/9

6/9

6/9

Mean Ct value of positives^c

26.18

28.78

31.44

33.77

35.72

35.55

35.59

Mean CV of Ct values (%)^d

0.78

0.84

0.71

1.85

2.28

-

-

Estimated wt DNA content (%)^e

5.00

0.82

0.13

0.026

0.0067

0.0075

0.0074

Bias (%)^f

0

-18

-35

-35

-16

371

819

^aSerial dilutions 1:5 of 5% wt soybean DNA in RR soybean DNA (weight/weight)

^bproportion of PCR replicates yielding a positive signal

^cmean of nine values

^dCV calculated among PCR replicates

^ebased on the calibration curve passing through the point corresponding to the 5% wt with the observed Ct (26.18) and theoretical slope of -3.32

^fdeviation (%) between estimated and expected wt DNA content

Battistini and Noli BMC Biotechnology 2009 9:16   doi:10.1186/1472-6750-9-16