Real-time quantification of wild-type contaminants in glyphosate tolerant soybean

BMC Biotechnology

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

ISSN: 1472-6750