Beckman Coulter CEQ 8000, Руководство пользователя

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Fragment Analysis Procedures
232 CEQ™ 8000 Genetic Analysis System
Peak Criteria
4. The
Slope Threshold
field allows you to specify the minimum rate of the signal
increase on the leading edge of peaks in order for a peak (standard or unknown) to
be detected.
• Enter a value between 1 - 1000. The default value is 10.
• The slope is proportional to the height of the peak and also dependent on
the width of the peak. This parameter can be set to detect peaks of interest
while eliminating smaller or broader peaks that may not be of interest.
• The slope threshold is set relative to the baseline noise, as the baseline noise
will vary for each dye trace.
•
Although only one slope threshold value is defined, the system will make
adjustments for each dye, depending on the noise detected for that dye
trace.
• The default value should be appropriate for most samples, however, if
peaks are “missed”, the threshold can be lowered.
5. The
Relative Peak Height Threshold (%)
field allows you to set a minimum
height criterion which unknown peaks must meet before being displayed in the
fragment list or annotated in fragment (trace) data.
• Enter a value between 0 - 100%. The default value is 10%.
• The unknown peaks above this set value (%) relative to the second highest
peak in each dye trace will be displayed in the fragment list and the sizes
will be displayed in the fragment (trace) data.
• This value does not apply to standards.
• To size the peaks only, make sure that the
Allele Identification
boxes
are
not checked
.
Allele Identification
6. If you would like the parameter set to include allele identification as specified in
the allele lists of the selected locus tags, select the
Identify STR Alleles
check
box.
7. If you would like to include Single Nucleotide Polymorphism (SNP) analysis in
the parameter set, select the
SNP Analysis
check box.
You may choose to identify STR Alleles or perform a SNP Analysis or
to do neither, but not both in the same analysis.
Confidence Level
8. Set the confidence level required for your analysis. The confidence level (default
value 95%) is equal to one minus the significance level of the built-in statistical
tests used for allele identification and for computing apparent fragment size
confidence intervals.