Chapter 6 | Working with Mapping Data
247
Loss of Heterozygosity Analysis
Loss of heterozygosity (LOH) studies compares the allele calls of the
SNPs in two different samples.
The LOH feature in the Mapping window allows you to survey all of
the SNPs in two selected samples for LOH.
The LOH is reported as a change in the SNP’s Relative Allele Signal
(RAS) values between two samples, A and B. It is calculated by the
formula:
where RAS
F
and RAS
R
are the forward and reverse RAS scores,
respectively.
To perform an LOH analysis for two samples:
1.
Click the
LOH
button
; or
Select
View
LOH
from the menu bar.
2.
Enter a title for the LOH column in the SNP Table where the
results will be displayed.
When analyzing data for Dynamic Model arrays, the LOH algorithm
calculates a relative allele score for each sample and SNP and then
uses the formula above to calculate the LOH scores. For MPAM
arrays, the RAS scores are metrics calculated as by the genotyping
algorithm.
You must display the Mapping analysis results for the samples you
wish to compare in the Mapping window to perform an LOH
analysis.
deltaRAS
RAS
FA
RAS
FB
–
(
)
2
RAS
FA
RAS
FB
–
(
)
2
+
=
GTYPE_manual.book Page 247 Wednesday, August 2, 2006 11:31 AM
Summary of Contents for iServer MicroServer iTHX-M
Page 9: ...Introduction GTYPE_manual book Page 1 Wednesday August 2 2006 11 31 AM...
Page 10: ...GTYPE_manual book Page 2 Wednesday August 2 2006 11 31 AM...
Page 19: ...Chapter 1 GTYPE Overview GTYPE_manual book Page 11 Wednesday August 2 2006 11 31 AM...
Page 20: ...Chapter 1 GTYPE_manual book Page 12 Wednesday August 2 2006 11 31 AM...
Page 55: ...Chapter 2 Getting Started GTYPE_manual book Page 47 Wednesday August 2 2006 11 31 AM...
Page 56: ...Chapter 2 GTYPE_manual book Page 48 Wednesday August 2 2006 11 31 AM...
Page 85: ...Chapter 3 Working with Images GTYPE_manual book Page 77 Wednesday August 2 2006 11 31 AM...
Page 86: ...Chapter 3 GTYPE_manual book Page 78 Wednesday August 2 2006 11 31 AM...
Page 114: ...Chapter 4 GTYPE_manual book Page 106 Wednesday August 2 2006 11 31 AM...
Page 145: ...Chapter 5 Mapping Analysis Window GTYPE_manual book Page 137 Wednesday August 2 2006 11 31 AM...
Page 146: ...Chapter 5 GTYPE_manual book Page 138 Wednesday August 2 2006 11 31 AM...
Page 188: ...Chapter 6 GTYPE_manual book Page 180 Wednesday August 2 2006 11 31 AM...
Page 259: ...Chapter 7 Universal Tag Window GTYPE_manual book Page 251 Wednesday August 2 2006 11 31 AM...
Page 260: ...Chapter 7 GTYPE_manual book Page 252 Wednesday August 2 2006 11 31 AM...
Page 269: ...Chapter 8 Probe Intensity Window GTYPE_manual book Page 261 Wednesday August 2 2006 11 31 AM...
Page 270: ...Chapter 8 GTYPE_manual book Page 262 Wednesday August 2 2006 11 31 AM...
Page 283: ...Chapter 9 NetAffx Annotations GTYPE_manual book Page 275 Wednesday August 2 2006 11 31 AM...
Page 284: ...Chapter 9 GTYPE_manual book Page 276 Wednesday August 2 2006 11 31 AM...
Page 297: ...Chapter 10 Reports GTYPE_manual book Page 289 Wednesday August 2 2006 11 31 AM...
Page 298: ...Chapter 10 GTYPE_manual book Page 290 Wednesday August 2 2006 11 31 AM...
Page 314: ...Appendix A GTYPE_manual book Page 306 Wednesday August 2 2006 11 31 AM...
Page 325: ...Appendix B MPAM Mapping Algorithm GTYPE_manual book Page 317 Wednesday August 2 2006 11 31 AM...
Page 326: ...Appendix B GTYPE_manual book Page 318 Wednesday August 2 2006 11 31 AM...
Page 344: ...Appendix C GTYPE_manual book Page 336 Wednesday August 2 2006 11 31 AM...
Page 362: ...Appendix D GTYPE_manual book Page 354 Wednesday August 2 2006 11 31 AM...
Page 385: ...Appendix E Mapping Tool Algorithms GTYPE_manual book Page 377 Wednesday August 2 2006 11 31 AM...
Page 386: ...Appendix E GTYPE_manual book Page 378 Wednesday August 2 2006 11 31 AM...
Page 393: ...Appendix F IUPAC Base Codes GTYPE_manual book Page 385 Wednesday August 2 2006 11 31 AM...
Page 394: ...Appendix F GTYPE_manual book Page 386 Wednesday August 2 2006 11 31 AM...
Page 397: ...Appendix G File Types GTYPE_manual book Page 389 Wednesday August 2 2006 11 31 AM...
Page 398: ...Appendix G GTYPE_manual book Page 390 Wednesday August 2 2006 11 31 AM...
Page 402: ...Appendix H GTYPE_manual book Page 394 Wednesday August 2 2006 11 31 AM...
Page 405: ...Appendix I Hot Key Descriptions GTYPE_manual book Page 397 Wednesday August 2 2006 11 31 AM...
Page 406: ...Appendix I GTYPE_manual book Page 398 Wednesday August 2 2006 11 31 AM...
Page 409: ...Index GTYPE_manual book Page 401 Wednesday August 2 2006 11 31 AM...
Page 410: ...GTYPE_manual book Page 402 Wednesday August 2 2006 11 31 AM...