Correlation between gene mutation status and selected clinical features
Acute Myeloid Leukemia (Primary blood derived cancer - Peripheral blood)
23 May 2013  |  analyses__2013_05_23
Maintainer Information
Citation Information
Maintained by TCGA GDAC Team (Broad Institute/MD Anderson Cancer Center/Harvard Medical School)
Cite as Broad Institute TCGA Genome Data Analysis Center (2013): Correlation between gene mutation status and selected clinical features. Broad Institute of MIT and Harvard. doi:10.7908/C1CV4FS9
Overview
Introduction

This pipeline computes the correlation between significantly recurrent gene mutations and selected clinical features.

Summary

Testing the association between mutation status of 7 genes and 3 clinical features across 196 patients, 3 significant findings detected with Q value < 0.25.

  • DNMT3A mutation correlated to 'Time to Death'.

  • U2AF1 mutation correlated to 'AGE'.

  • IDH2 mutation correlated to 'AGE'.

Results
Overview of the results

Table 1.  Get Full Table Overview of the association between mutation status of 7 genes and 3 clinical features. Shown in the table are P values (Q values). Thresholded by Q value < 0.25, 3 significant findings detected.

Clinical
Features
Time
to
Death
AGE GENDER
nMutated (%) nWild-Type logrank test t-test Fisher's exact test
DNMT3A 51 (26%) 145 0.000405
(0.00811)
0.0653
(1.00)
0.328
(1.00)
U2AF1 8 (4%) 188 0.614
(1.00)
0.00137
(0.026)
0.0703
(1.00)
IDH2 20 (10%) 176 0.448
(1.00)
1.11e-05
(0.000233)
0.815
(1.00)
FLT3 56 (29%) 140 0.085
(1.00)
0.563
(1.00)
0.754
(1.00)
IDH1 19 (10%) 177 0.81
(1.00)
0.304
(1.00)
0.633
(1.00)
NPM1 54 (28%) 142 0.112
(1.00)
0.968
(1.00)
0.262
(1.00)
NRAS 15 (8%) 181 0.851
(1.00)
0.287
(1.00)
1
(1.00)
'DNMT3A MUTATION STATUS' versus 'Time to Death'

P value = 0.000405 (logrank test), Q value = 0.0081

Table S1.  Gene #1: 'DNMT3A MUTATION STATUS' versus Clinical Feature #1: 'Time to Death'

nPatients nDeath Duration Range (Median), Month
ALL 172 107 0.9 - 94.1 (12.0)
DNMT3A MUTATED 46 35 0.9 - 37.0 (9.0)
DNMT3A WILD-TYPE 126 72 0.9 - 94.1 (15.0)

Figure S1.  Get High-res Image Gene #1: 'DNMT3A MUTATION STATUS' versus Clinical Feature #1: 'Time to Death'

'U2AF1 MUTATION STATUS' versus 'AGE'

P value = 0.00137 (t-test), Q value = 0.026

Table S2.  Gene #2: 'U2AF1 MUTATION STATUS' versus Clinical Feature #2: 'AGE'

nPatients Mean (Std.Dev)
ALL 196 55.1 (16.2)
U2AF1 MUTATED 8 69.9 (9.0)
U2AF1 WILD-TYPE 188 54.5 (16.1)

Figure S2.  Get High-res Image Gene #2: 'U2AF1 MUTATION STATUS' versus Clinical Feature #2: 'AGE'

'IDH2 MUTATION STATUS' versus 'AGE'

P value = 1.11e-05 (t-test), Q value = 0.00023

Table S3.  Gene #4: 'IDH2 MUTATION STATUS' versus Clinical Feature #2: 'AGE'

nPatients Mean (Std.Dev)
ALL 196 55.1 (16.2)
IDH2 MUTATED 20 64.8 (8.0)
IDH2 WILD-TYPE 176 54.0 (16.5)

Figure S3.  Get High-res Image Gene #4: 'IDH2 MUTATION STATUS' versus Clinical Feature #2: 'AGE'

Methods & Data
Input
  • Mutation data file = LAML-TB.mutsig.cluster.txt

  • Clinical data file = LAML-TB.clin.merged.picked.txt

  • Number of patients = 196

  • Number of significantly mutated genes = 7

  • Number of selected clinical features = 3

  • Exclude genes that fewer than K tumors have mutations, K = 3

Survival analysis

For survival clinical features, the Kaplan-Meier survival curves of tumors with and without gene mutations were plotted and the statistical significance P values were estimated by logrank test (Bland and Altman 2004) using the 'survdiff' function in R

Student's t-test analysis

For continuous numerical clinical features, two-tailed Student's t test with unequal variance (Lehmann and Romano 2005) was applied to compare the clinical values between tumors with and without gene mutations using 't.test' function in R

Fisher's exact test

For binary or multi-class clinical features (nominal or ordinal), two-tailed Fisher's exact tests (Fisher 1922) were used to estimate the P values using the 'fisher.test' function in R

Q value calculation

For multiple hypothesis correction, Q value is the False Discovery Rate (FDR) analogue of the P value (Benjamini and Hochberg 1995), defined as the minimum FDR at which the test may be called significant. We used the 'Benjamini and Hochberg' method of 'p.adjust' function in R to convert P values into Q values.

Download Results

This is an experimental feature. The full results of the analysis summarized in this report can be downloaded from the TCGA Data Coordination Center.

References
[1] Bland and Altman, Statistics notes: The logrank test, BMJ 328(7447):1073 (2004)
[2] Lehmann and Romano, Testing Statistical Hypotheses (3E ed.), New York: Springer. ISBN 0387988645 (2005)
[3] Fisher, R.A., On the interpretation of chi-square from contingency tables, and the calculation of P, Journal of the Royal Statistical Society 85(1):87-94 (1922)
[4] Benjamini and Hochberg, Controlling the false discovery rate: a practical and powerful approach to multiple testing, Journal of the Royal Statistical Society Series B 59:289-300 (1995)