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Presented by: Andrew McMurry Boston University Bioinformatics Children’s Hospital Informatics Program Harvard Medical School Center for BioMedical Informatics This Presentation Available at: http://pixelshelf.com/~justandy/f-snp.ppt. Outline.
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Presented by: Andrew McMurryBoston University BioinformaticsChildren’s Hospital Informatics Program Harvard Medical School Center for BioMedical InformaticsThis Presentation Available at: http://pixelshelf.com/~justandy/f-snp.ppt
Outline • Incidental Findings and Disconnected Patient Cohorts • Disease Association Studies Using SNPs • How SNPs cause disease • Computationally predict affect of SNPs within introns, exons, and regulatory regions • The Future Is Now: SNPs, Personalized Medicine, and Translational Research
Incidental Findings and Disconnected Patient Cohorts • IF the central dogma of Biology is: • “From DNA ->RNA ->Protein” • THEN where is the patient data for association studies? • Very little patient data spanning DNA/RNA/ protein/phenotype across a single cohort • Need to obtain “robust” sample sizes to avoid incidental findings due to multiple testing [1] [1] Isaac Kohane, Daniel Masys, and Russ Altman. "The Incidentalome: A Threat to Genomic Medicine" JAMA 296(2): 212-215. July 12, 2006.
Disease Association Studies Using SNPs • DNA sequencing technologies still very expensive • Stunningly few patients • Minimal sequence coverage • Could change in time with Solexa/454 • Even with solexa/454 there is a massive task of piecing together the results (often max sequence read shorter than single repeated gene) • Rate limiting step: Adoption rate of DNA sequencing • Use what is available in abundance! SNP chips • Abundance of SNP chips in public repos on many diseases • Whole genome coverage 500k SNPs for $250
Disease Association Studies Using SNPs • DNA to RNA to Protein • Associating DNA & RNA • GEO alone well over 100k Gene Expression Arrays • What if we could correlate SNPs affect on Gene Expression? • Associating DNA & Gene Product (protein) • Countless public protein databases • What if we could correlate SNPs affect on Protein Coding? • Association studies involving multiple genomic measurements • What are the existing studies and models (HMMs/Bayes nets) that could be strengthened with evidence from SNP chips?
How SNPs cause disease • Intron • Likely no affect • Protein Coding • Missense • Synonymous Same Amino Acid • Non Synonymous Different Amino Acid • Nonsense • Premature STOP • Splicing Regulation • Incorrect final mRNA transcript • Transcriptional Regulation • Differential gene expression • Post Translational • Protein phosphorylation
F-SNP : integrated approach 1. Classify SNP site using dbSNP • Intron • Coding Region • Splice Site • TF binding Site • Post-Translational Site 2. Evaluate using the specialized algorithms/dbs • Coding region (missense/nonsense mutations) • Splice Site (intronic/exonic sites) • TF binding Site (promoter/repressor/etc) • Post-Translational Site (Phospho/Tyrosine/0-glycosylation) 3. “Majority Vote” across algorithms
F-SNP: User Interfaces & Data Download • Public Web Site • Federated Query = entire database cannot be downloaded • Currently: • no SOAP (webservice) support • no RSS support • No source code available • However: • Paper gives explicit instructions on how to reproduce the algorithm and construct the database using dbSNP, OMIM, etc.
SNP Primary Information (rs28897699) • Locus • Alleles • Ancestral Allele • Validation (if any) • Region • Link to References
F-SNP Prediction Detail:PolyPhen = benign affect on protein coding
F-SNP Prediction Detail:SNPs3D = deleterious to protein coding NCBI Gene Information Productbreast cancer 1, early onsetOther names,BRCA1,BRCAI,BRCC1,IRIS,PSCP,RNF53NCBI Entrez Gene Summary: This gene encodes a nuclear phosphoprotein that plays a role in maintaining genomic stability and acts as a tumor suppressor. (…) Mutations in this gene are responsible for approximately 40% of inherited breast cancers and more than 80% of inherited breast and ovarian cancers.Alternative splicing plays a role in modulating the subcellularlocalization and physiological function of this gene. Many alternatively spliced transcript variants have been described for this gene but only some have had their full-length natures identified. (…)
F-SNP functional prediction • on Protein Coding 2 votes benign, 1 deleterious, 1 nonsynonymous • on Splicing Regulation predictedfunctional impact (by majority vote)
Gene level view of BRCA1 • Query by gene name = “BRCA1” • Returns list of SNPs in BRCA1 • Returns list of Cancers associated with BRCA1
Gene level view of BRCA1 • our SNP has functional impact • our SNP has neighboring functional SNPS
Disease Level View : Breast Cancer • Show all disease genes associated with breast cancer • Denote if SNPs are present in those genes (5k up/downstream)
The Future Is Now: SNPs, Personalized Medicine, and Translational Research • SNP profiling becoming part of routine care [2] • Increase # of clinically annotated SNP chips Increase # of disease association studies using SNPs • Increase in NIH focus on “translational research” that bridges routine care delivery with research efforts • Genome Wide Association Studies (GWAS) that actually get funded [2] Kohane IS, Mandl KD, Taylor PL, Holm IA, Nigrin DJ, Kunkel “LM. Medicine. Reestablishing the researcher-patient compact.” Science. 2007 Nov 16;318(5853):1068.
F-SNP Summary • Incidental Findings and Disconnected Patient Cohorts • Central dogma of biology DNA->RNA-Protein, yet we lack cohort spans all measurements • Using limited sample size will inevitably lead to incidental outcomes • Disease Association Studies Using SNPs • Don’t wait for DNA sequencing to become widespread • SNPs are becoming an abundant resource and not going to disappear • How SNPs cause disease • Protein Coding • Splicing Regulation • Transcription Regulation • Post Translation • Computationally predict affect of SNPs within introns, exons, and regulatory regions • Multitude of existing SNP analysis tools and resources • F-SNP provides a single web based resource to mine SNP disease associations • Query and analysis by SNP, Gene, Disease • The role of SNPs in Personalized Medicine & and Translational Research