SMR (Summary-based Mendelian Randomization) software integrates summary-level data from genome-wide association studies (GWAS) with data from expression quantitative trait locus (eQTL) studies to identify genes whose expression levels are associated with a complex trait because of pleiotropy. It implements the SMR & HEIDI methods to test for pleiotropic association between the expression level of a gene and a complex trait of interest using summary-level data from GWAS and expression quantitative trait loci (eQTL) studies (Zhu et al. 2016 Nat Genet). The methodology can be interpreted as an analysis to test if the effect size of a SNP on the phenotype is mediated by gene expression. This tool can therefore be used to prioritize genes underlying GWAS hits for follow-up functional studies.
Allocate an interactive session and run the program. Sample session:
[user@biowulf]$ sinteractive salloc.exe: Pending job allocation 46116226 salloc.exe: job 46116226 queued and waiting for resources salloc.exe: job 46116226 has been allocated resources salloc.exe: Granted job allocation 46116226 salloc.exe: Waiting for resource configuration salloc.exe: Nodes cn3144 are ready for job [user@cn3144 ~]$ module load SMR [+] Loading SMR 1.03 [user@cn3144 ~]$ smr --beqtl-summary $SMR_DIR/TEST_DATA/westra_eqtl_hg18 --query 5.0e-8 --snp rs123 ******************************************************************* * Summary-data-based Mendelian Randomization (SMR) * version 1.03 * (C) 2015 Futao Zhang, Zhihong Zhu and Jian Yang * The University of Queensland * MIT License ******************************************************************* Analysis started: 13:27:52,Tue Sep 29,2020 Options: --beqtl-summary /usr/local/apps/SMR/TEST_DATA/westra_eqtl_hg18 --query 5.00e-08 --snp rs123 Reading eQTL summary data... Reading eQTL probe information from [/usr/local/apps/SMR/TEST_DATA/westra_eqtl_hg18.epi]. 5967 Probes to be included from [/usr/local/apps/SMR/TEST_DATA/westra_eqtl_hg18.epi]. Reading eQTL SNP information from [/usr/local/apps/SMR/TEST_DATA/westra_eqtl_hg18.esi]. 506193 SNPs to be included from [/usr/local/apps/SMR/TEST_DATA/westra_eqtl_hg18.esi]. rs123 is extracted. Reading eQTL summary data from [/usr/local/apps/SMR/TEST_DATA/westra_eqtl_hg18.besd]. This is an old file format. Please use --make-besd to update the file format. eQTL summary data of 5967 Probes and 1 SNPs to be included from [/usr/local/apps/SMR/TEST_DATA/westra_eqtl_hg18.besd]. Extracted results of 1 SNPs have been saved in the file [smr.txt]. Analysis completed: 13:27:53,Tue Sep 29,2020 Computational time: 0:0:1 [user@cn3144 ~]$ cat smr.txt SNP Chr BP A1 A2 Freq Probe Probe_Chr Probe_bp Gene Orientation b SE p rs123 7 24932971 A C NA ILMN_1670145 7 24704613 DFNA5 - 0.117336 0.0193413 1.30632e-09 [user@cn3144 ~]$ exit salloc.exe: Relinquishing job allocation 46116226 [user@biowulf ~]$
Create a batch input file (e.g. SMR.sh). For example:
#!/bin/bash module load SMR smr --beqtl-summary $SMR_DIR/TEST_DATA/westra_eqtl_hg18 --query 5.0e-8 --snp rs123
Submit this job using the Slurm sbatch command.
sbatch [--cpus-per-task=#] [--mem=#] SMR.sh