ABI Prism® 7900HT Sequence Detection System ... - OpenWetWare

5-14 End-Point Analysis
To analyze allele types: (continued)
Step Action
3 Screen for Unknown samples that failed to amplify:
a. From the Allelic Discrimination Plot, select the NTC cluster.
The SDS software highlights the datapoints within the allele plot and the plate
grid.
b. From the plate grid, check the wells containing Unknown samples for selected
wells that are clustered with the NTCs.
Samples that clustered with the No Template Control wells may:
♦ Contain no DNA
♦ Contain PCR inhibitors
♦ Be homozygous for a sequence deletion
NTC cluster
(selected)
No Template
Control wells
Unknown samples
clusteredwiththeNTCs
4 Retest any samples that did not cluster tightly or clustered with NTCs to confirm the
results.
5 If evaluating for multiple markers, do the following:
a. From the Marker drop-down list, select a different marker.
b. Repeat steps 1 to 4 for the new marker.
c. Repeat steps a and b until the calls for each marker have been verified.