Accessing the 1000 Genomes Data Paul Flicek European BioinformaMcs InsMtute Data access • • • • • General informaMon File access 1000 Genomes Browser Tools Where to find help www.1000genomes.org www.1000genomes.org 1000 Genomes Project Resources L. Clarke, H. Zheng-Bradley, R. Smith, E Kuleshea, I Toneva, B. Vaughan, P. Flicek and 1000 Genomes Consortium European Bioinformatics Institute, Wellcome Trust Genome Campus, Cambridge, CB10 1SA, UK Introduction DATA TYPE FILE FORMAT SIZE sequence FASTQ alignment BAM 56 Tbytes of BAM files variants VCF 38.9M SNPs ~4.7M short indels http://browser.1000genomes.org The 1000 Genomes project utilizes the Ensembl Browser to display our variant calls. We provide rapid access to project variant calls through the browser before they become available via dbSNP and DGVa. Tracks of 1000 genomes variants by population can be viewed in the location page: Variant Effect Predictor The predictor takes a list of variant positions and alleles, and predicts the effects of each of these on any overlapping features (transcripts, regulatory features) annotated in Ensembl. An example output is shown below: Data Slicer Many of the 1000 Genomes files are large and cumbersome to handle. The Data Slicer allows users to get data for specific regions of the genome and to avoid having to download many gigabytes of data they don’t needl samples/ populations you choose. Below is the Data Slicer input interface: Discoverability The ftp site has a index updated nightly. This index is searchable from our website. http://www.1000genome.org/ftpsearch A list of variants can be obtained for any given transcript. In addition to basic information about a variant, PolyPhen and SIFT annotation are displayed to indicate the clinic significance of the variant. The search allows users to specify which ftp site to get paths to, to get md5 checksums and also filter out high volume results like bam and Allele frequency for individual variants in different populations is displayed fastq files on the ‘Population Genetics’ page. We also have various routes for users to discover new data. Variation Pattern Finder • The Variation Pattern Finder (VPF) allows one to look for patterns of shared variation between individuals in the a VCF file. • Within a vcf file different samples have different combination of variation genotypes. The VPF looks for distinct variation combinations within a user specifed region, shared by different individuals. • The VPF only on variations that functional consequences for protein coding genes such as non-synonymous coding SNPs and splice site changes. Users can Attach remote files as custom tracks. In example below, the HG00120 track is 1000 Genomes bam file added to the browser. Website http://www.1000genomes.org/announcements Twitter @1000genomes RSS http://www.1000genomes.org/announcements/rss.xml Email [email protected] Laura Clarke EBI [email protected] http://browser.1000genomes.org/tools.html The project provides several tools to help users access and interpret the data provided. 43 Tbases raw sequence Sequence, alignment and variant data is made available as quickly as possible through the project ftp site. (ftp://ftp.1000genomes.ebi.ac.uk/vol1/ftp/ | ftp://ftp-trace.ncbi.nih.gov/1000genomes/). With more than 200,000 files though discovering new data can be difficult. • • • • Accessibility Visualization The main goal of the 1000 genomes project is to establish a comprehensive and detailed catalogue of human genome variations; which in turn will empower association studies to identify disease-causing genes. The project now has data and variant genotypes for more than 1000 individuals in 14 populations. The ftp site contains more than 120Tbytes of data in 200,000 files. Acknowledgements We would like to thank the Ensembl variation team for all their help, particularly Will McLaren and Graham Ritchie. Funding: The Wellcome Trust EMBL- EBI Wellcome Trust Genome Campus Hinxton Cambridge CB10 1SD UK T +44 (0) 1223 494 444 F +44 (0) 1223 494 468 http://www.ebi.ac.uk Data access • • • • • General informaMon File access 1000 Genomes Browser Tools Where to find help >p://>p.1000genomes.ebi.ac.uk >p://>p‐trace.ncbi.nih.gov/1000genomes/>p Site documentaMon Sequences & alignments by sample ID Data sets to accompany the pilot data publicaMon. Current and archive data set releases Pre‐release data sets and project working materials BIOINFORMATICS APPLICATIONS NOTE Sequence analysis Vol. 25 no. 16 2009, pages 2078–2079 doi:10.1093/bioinformatics/btp352 Data formats and key tools The Sequence Alignment/Map format and SAMtools Heng Li1,† , Bob Handsaker2,† , Alec Wysoker2 , Tim Fennell2 , Jue Ruan3 , Nils Homer4 , Gabor Marth5 , Goncalo Abecasis6 , Richard Durbin1,∗ and 1000 Genome Project Data Processing Subgroup7 1 Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, CB10 1SA, UK, 2 Broad Institute of MIT and Harvard, Cambridge, MA 02141, USA, 3 Beijing Institute of Genomics, Chinese Academy of Science, Beijing 100029, China, 4 Department of Computer Science, University of California Los Angeles, Los Angeles, CA 90095, 5 Department of Biology, Boston College, Chestnut Hill, MA 02467, 6 Center for Statistical Genetics, Department of Biostatistics, University of Michigan, Ann Arbor, MI 48109, USA and 7 http://1000genomes.org Received on April 28, 2009; revised on May 28, 2009; accepted on May 30, 2009 Advance Access publication June 8, 2009 BAM alignment files Associate Editor: Alfonso Valencia 2 METHODS 2.1 The SAM format 2.1.1 Overview of the SAM format The SAM format consists of one header section and one alignment section. The lines in the header section start with character ‘@’, and lines in the alignment section do not. All lines are TAB delimited. An example is shown in Figure 1b. In SAM, each alignment line has 11 mandatory fields and a variable number of optional fields. The mandatory fields are briefly described in Table 1. They must be present but their value can be a ‘*’ or a zero (depending on the field) if the corresponding information is unavailable. The optional fields are presented as key-value pairs in the format of TAG:TYPE:VALUE. They store extra information from the platform or aligner. For example, the ‘RG’ tag keeps the ‘read group’ information for each read. In combination Sequence analysis with the ‘@RG’ header lines, this tag allows each read to be labeled with metadata about its origin, sequencing center and library. The SAM format 1 INTRODUCTION specification gives a detailed description of each field and the predefined With the advent of novel sequencing technologies such as TAGs. BIOINFORMATICS APPLICATIONS NOTE The variant call format and VCFtools Downloaded from bioinformatics.oxfordjournals.org at Genome Research Ltd on October 13, 2011 ABSTRACT Summary: The Sequence Alignment/Map (SAM) format is a generic alignment format for storing read alignments against reference sequences, supporting short and long reads (up to 128 Mbp) produced by different sequencing platforms. It is flexible in style, compact in size, efficient in random access and is the format in which alignments from the 1000 Genomes Project are released. SAMtools implements various utilities for post-processing alignments in the SAM format, such as indexing, variant caller and alignment viewer, and thus provides universal tools for processing read alignments. Availability: http://samtools.sourceforge.net Contact: [email protected] Vol. 27 no. 15 2011, pages 2156–2158 doi:10.1093/bioinformatics/btr330 Advance Access publication June 7, 2011 VCF variant files Illumina/Solexa, AB/SOLiD and Roche/454 (Mardis, 2008), a 1,† , Adam Auton2,† , Goncalo Abecasis3 , Cornelis A. Albers1 , Eric Banks4 , Petr Danecek variety of new alignment tools (Langmead et al., 2009; Li et al., 4 , Extended 4 , Gerton 2 , Gabor T. Marth5 , 2.1.2 The standard CIGAR descriptionLunter of pairwise RobertCIGAR E. Handsaker Mark A. DePristo 2008) have been designed to realize efficient read mapping against alignment defines three operations: 2,7 ‘M’ for match/mismatch, ‘I’ for insertion 6 , Gilean 1,∗ and 1000 Genomes Project McVean , Richard Durbin Stephen T. Sherry large reference sequences, including the human genome. These tools compared with the reference and ‘D’ for deletion. The extended CIGAR Vol. 27 no. 5 2011, pages 718–719 generate alignments in different formats, however, complicating proposed in SAM added four more operations: ‘N’ for skipped bases on Analysis Group‡ doi:10.1093/bioinformatics/btq671 the reference, ‘S’ for soft clipping, ‘H’ for hard clipping and ‘P’ for padding. downstream processing. A common alignment format that supports 1 Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge CB10 1SA, 2 Wellcome Trust Centre These support splicing, clipping, multi-part and padded alignments. Figure 1 all sequence types and aligners creates a well-defined interface 3 Center for Human Genetics,shows University ofof Oxford, Oxford OX3 7BN, UK, for Statistical Genetics, Department of examples CIGAR strings for different types of alignments. between alignment and downstream analyses, including variant Biostatistics, University of Michigan, Ann Arbor, MI 48109, 4 Program in Medical analysis and Population Genetics, Broad Sequence Advance Access publication January 5, 2011 detection, genotyping and assembly. 5 Department of Biology, Boston College, MA 02467, 6 National Institute of MITtoand 2.1.3 Harvard, Cambridge, MA 02141, Binary Alignment/Map format To improve the performance, we The Sequence Alignment/Map (SAM) format is designed 7 Institutes of Health National forformat Biotechnology Information, 20894, designed a Center companion Binary Alignment/Map (BAM),MD which is the USA and Department of Statistics, achieve this goal. It supports single- and paired-end reads and representation of SAM University Oxford,binary Oxford OX1 3TG, UK and keeps exactly the same information as combining reads of different types, including color space readsoffrom SAM. BAM is compressed by the BGZF library, a generic library developed Associate John Quackenbush AB/SOLiD. It is designed to scale to alignment sets of 1011Editor: or more by us to achieve fast random access in a zlib-compatible compressed file. base pairs, which is typical for the deep resequencing of one human An example alignment of 112 Gbp of Illumina GA data requires 116 GBLi of Heng individual. disk space (1.0 byte per input base), including sequences,Although base qualities and feature format (GFF) has recently been extended ABSTRACT generic Program Population Genetics, The Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA In this article, we present an overview of the SAM format and all the meta information generated by MAQ. Most of this space is used toin Medical to standardize storage of variant information in genome variant Summary: The variant call format (VCF) is a generic format for briefly introduce the companion SAMtools software package. A Editor:etDmitrij Frishman storedata the base format Associate (GVF) (Reese al., 2010), this is not tailored for storing storing DNA polymorphism suchqualities. as SNPs, insertions, deletions detailed format specification and the complete documentation of information across many samples. We have designed the VCF and structural variants, together with rich annotations. VCF is usually SAMtools are available at the SAMtools web site. 2.1.4 Sorting and indexing A SAM/BAM file can beformat unsorted,tobut besorting scalable so as to encompass millions of sites with BIOINFORMATICS APPLICATIONS NOTE Tabix: fast retrieval of sequence features from generic TAB-delimited files Downloaded from bioinformatics.oxfordjournals.org at Genome Rese All indexed for fast retrieval stored in a compressed manner and can be indexed for fast data ABSTRACT by coordinate is used to streamline processing and to avoid loading genotype data and annotations from thousands of samples. We have retrieval of variants from a range of positions on the data reference Tabix is the first generic tool that indexes position sorted whom correspondence should be addressed. extra alignments into memory. A position-sorted BAMadopted file canSummary: be indexed.encoding, a textual with complementary indexing, to allow The format was developed for the 1000 Genomes Project, † The authors wish it to be known that, in their opinion,genome. the first two authors TAB-delimited formats such as GFF, BED, PSL, SAM and We combine the UCSC binning scheme (Kent et al., 2002)files andinsimple easy generation of the files while maintaining fast data access. and has also been adopted by other projects such as UK10K, should be regarded as Joint First Authors. linear indexing to achieve fast random retrieval of alignments overlapping a and quickly retrieves features overlapping specified SQL export, In this article, we present an overview of the VCF and briefly dbSNP and the NHLBI Exome Project. VCFtools is a software suite regions. Tabix features include few seek function calls per query, data introduce the companion VCFtools software package. A detailed that implements various utilities for processing VCF files, including compression with gzip compatibility and direct FTP/HTTP access. format specification and the complete documentation of VCFtools validation, merging, comparing and also provides a general Perl API. © 2009 The Author(s) Tabix is implemented as a free command-line tool as well as a library are available at the VCFtools web site. Availability: http://vcftools.sourceforge.net This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ in C, Java, Perl and Python. It is particularly useful for manually Contact: [email protected] by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. examining local genomic features on the command line and enables 2 METHODS genome viewers to support huge data files and remote custom tracks Received on October 28, 2010; revised on May 4, 2011; accepted ∗ To 2 METHODS Tabix indexing is a generalization of BAM indexing for generic TABdelimited files. It inherits all the advantages of BAM indexing, including data compression and efficient random access in terms of few seek function calls per query. 2.1 Sorting and BGZF compression Before being indexed, the data file needs to be sorted first by sequence name and then by leftmost coordinate, which can be done with the standard Unix sort. The sorted file should then be compressed with the bgzip program 1000 Genomes is in the Amazon cloud 1KG pilot content (BAM) is available at s3://1000genomes.s3.amazonaws.com You can see the XML at hOp://1000genomes.s3.amazonaws.com Data access • • • • • General informaMon File access 1000 Genomes Browser Tools Where to find help hOp://browser.1000genomes.org • Gene variaMon zoom • PopulaMon • SIFT • PolyPhen File upload to view with 1000 Genomes data • Supports popular file types: – BAM, BED, bedGraph, BigWig, GBrowse, Generic, GFF, GTF, PSL, VCF*, WIG * VCF must be indexed Uploaded VCF Example: Comparison of August calls and /technical/working/20110502_vqsr_phase1_wgs_snps/ALL.wgs.phase1.projectConsensus.snps.sites.vcf.gz 1000 Genomes Browser • For further informaMon on the capabiliMes of the browser and its use, aOend the Ensembl “New Users” Workshop on Saturday at 12:30 hOp://pilotbrowser.1000genomes.org Data access • • • • • General informaMon File access 1000 Genomes Browser Tools Where to find help hOp://browser.1000genomes.org Tools page Ensembl Variant Effector Predictor (VEP) • Takes list of variaMon and annotates with respect to Ensembl features • Returns whether the SNP has been seen in the 1000 Genomes and if it has an rs number (if one has been assigned) • Returns SIFT, PolyPhen and Condel scores • Extensive filtering opMons by MAF and populaMons • Web and command line versions Data slicer for subsets of the data hOp://trace.ncbi.nlm.nih.gov/Traces/1kg_slicer/ Sliced BAM to files VariaMon PaOern Finder • hOp://browser.1000genomes.org/ Homo_sapiens/UserData/VariaMonsMapVCF • VCF input • Discovers paOerns of Shared Inheritance • Variants with funcMonal consequences considered • Web output with csv and excel downloads Access to backend Ensembl databases • Public MySQL database at – mysql‐db.1000genomes.org port 4272 • Full programmaMc access with Ensembl API – More informaMon on the use of the Ensembl API at the Ensembl “Advanced Users” Workshop tomorrow Data access • • • • • General informaMon File access 1000 Genomes Browser Tools Where to find help Credits & Contact • Eugene Kulesha, Iliana Toneva, Bren Vaughan • Will McLaren, Graham Ritchie, Fiona Cunningham • Laura Clarke, Holly Zheng-Bradley, Rick Smith • Steve Sherry, Chunlin Xiao For more information contact [email protected]
© Copyright 2024