Correlations between copy number and mRNAseq expression
Kidney Chromophobe (Primary solid tumor)
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): Correlations between copy number and mRNAseq expression. Broad Institute of MIT and Harvard. doi:10.7908/C1125QN5
Overview
Introduction

A TCGA sample is profiled to detect the copy number variations and expressions of genes. This pipeline attempts to correlate copy number and Rnaseq data of genes across samples to determine if the copy number variations also result in differential expressions. This report contains the calculated correlation coefficients based on measurements of genomic copy number (log2) values and RNAseq expression of the corresponding feature across patients. High positive/low negative correlation coefficients indicate that genomic alterations result in differences in the expressions of mRNAseq the genomic regions transcribe.

Summary

The correlation coefficients in 10, 20, 30, 40, 50, 60, 70, 80, 90 percentiles are 847.7, 2097, 2735, 3338, 3913.5, 4502, 5106, 5746, 6503.3, respectively.

Results
Correlation results

Number of genes and samples used for the calculation are shown in Table 1. Figure 1 shows the distribution of calculated correlation coefficients and quantile-quantile plot of the calculated correlation coefficients against a normal distribution. Table 2 shows the top 20 features ordered by the value of correlation coefficients.

Table 1.  Counts of mRNAseq and number of samples in copy number and expression data sets and common to both

Category Copy number Expression Common
Sample 66 66 66
Genes 23778 17843 17758

Figure 1.  Summary figures. Left: histogram showing the distribution of the calculated correlations across samples for all Genes. Right: QQ plot of the calculated correlations across samples. The QQ plot is used to plot the quantiles of the calculated correlation coefficients against that derived from a normal distribution. Points deviating from the blue line indicate deviation from normality.

Table 2.  Get Full Table Top 20 features (defined by the feature column) ranked by correlation coefficients

Locus ID Gene Symbol Cytoband cor p-value q-value
23185 LARP4B 10p15.3 0.8249 0 0
6945 MLX 17q21.2 0.8134 0 0
83607 AMMECR1L 2q14.3 0.8125 0 0
55571 C2orf29 2q11.2 0.7908 2.66453525910038e-15 4.59971017089701e-12
84991 RBM17 10p15.1 0.7886 3.77475828372553e-15 5.21300486034994e-12
51021 MRPS16 10q22.2 0.7867 4.88498130835069e-15 5.62186798665189e-12
54619 CCNJ 10q24.1 0.7831 7.99360577730113e-15 7.66618361816167e-12
7327 UBE2G2 21q22.3 0.7821 8.88178419700125e-15 7.66618361816167e-12
23181 DIP2A 21q22.3 0.78 1.19904086659517e-14 9.19942034179401e-12
5211 PFKL 21q22.3 0.7628 9.85878045867139e-14 6.80757105292757e-11
284948 SH2D6 2p11.2 0.7596 1.76249098293724e-06 1.39406058199012e-05
56888 KCMF1 2p11.2 0.7595 1.4432899320127e-13 9.06003518510016e-11
22993 HMGXB3 5q32 0.7569 1.95843341543878e-13 1.12692899186977e-10
57700 FAM160B1 10q25.3 0.7487 4.90052443069544e-13 2.55174397575953e-10
670 BPHL 6p25.2 0.7482 5.17363929475323e-13 2.55174397575953e-10
645027 EVPLL 17p11.2 0.7465 3.31714393020377e-06 2.29518619004447e-05
1876 E2F6 2p25.1 0.7397 1.29585231434248e-12 5.70172406600775e-10
617 BCS1L 2q35 0.7395 1.32116539930394e-12 5.70172406600775e-10
8575 PRKRA 2q31.2 0.7375 1.63558055987778e-12 6.35526621945603e-10
3241 HPCAL1 2p25.1 0.7374 1.65667479734566e-12 6.35526621945603e-10
Methods & Data
Input

Gene level (TCGA Level III) mRNAseq expression data and copy number data of corresponding gene derived by GISTIC pipelinePearson correlation coefficients were calculated for each pair of genes shared by the two data sets across all the samples that were common.

Correlation across sample

Pairwise correlations between the log2 copy numbers and expressions of each gene across samples were calculated using Pearson correlation.

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.