Correlations between copy number and mRNAseq expression
Cholangiocarcinoma (Primary solid tumor)
17 October 2014  |  analyses__2014_10_17
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 (2014): Correlations between copy number and mRNAseq expression. Broad Institute of MIT and Harvard. doi:10.7908/C10P0XVB
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 966.4, 2030.8, 2765, 3405.6, 4058, 4695.4, 5379, 6113.2, 6935, 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 36 36 36
Genes 24776 18131 15515

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
5987 TRIM27 6p22.1 0.9205 1.99840144432528e-15 3.10051984087067e-11
55585 UBE2Q1 1q21.3 0.9136 7.54951656745106e-15 1.17123200027436e-10
8315 BRAP 12q24.12 0.911 1.24344978758018e-14 1.92896365547313e-10
57505 AARS2 6p21.1 0.9098 1.55431223447522e-14 2.41104913811796e-10
57122 NUP107 12q15 0.8985 1.0413891970984e-13 1.61529878361932e-09
79882 ZC3H14 14q31.3 0.8934 2.30482299912182e-13 3.57478047163795e-09
11336 EXOC3 5p15.33 0.8893 4.2410519540681e-13 6.57744747556421e-09
5356 PLRG1 4q31.3 0.8835 9.62341317745086e-13 1.49239891555908e-08
9878 TOX4 14q11.2 0.883 1.0413891970984e-12 1.61488222794048e-08
55671 SMEK1 14q32.12 0.8799 1.56719082156087e-12 2.43008608791229e-08
8089 YEATS4 12q15 0.8751 2.96740410021812e-12 4.60096005738819e-08
220064 ORAOV1 11q13.3 0.8685 6.755929149449e-12 1.04743925533057e-07
11052 CPSF6 12q15 0.8682 6.98907598462029e-12 1.08351644989568e-07
55249 YY1AP1 1q22 0.8681 7.04192260059244e-12 1.09163884154384e-07
57862 ZNF410 14q24.3 0.8676 7.4602546362712e-12 1.1564140711684e-07
9587 MAD2L1BP 6p21.1 0.8674 7.70938868299709e-12 1.19495524586455e-07
261726 TIPRL 1q24.2 0.8672 7.86148923737073e-12 1.21845221690009e-07
9474 ATG5 6q21 0.8672 7.86659626328401e-12 1.21916508888376e-07
64710 NUCKS1 1q32.1 0.8666 8.41549052665869e-12 1.3041485669163e-07
5822 PWP2 21q22.3 0.8662 8.86513085163187e-12 1.37374067676888e-07
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

In addition to the links below, the full results of the analysis summarized in this report can also be downloaded programmatically using firehose_get, or interactively from either the Broad GDAC website or TCGA Data Coordination Center Portal.