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Biology subjects

Haoyang Zeng

Publications and source records attributed to Haoyang Zeng.

4 recordsLinked to original sources

Discovering DNA motifs and genomic variants associated with DNA methylation

DNA methylation plays a crucial role in establishing tissue-specific gene expression. However, our incomplete understanding of the cis elements that regulate DNA methylation prevents us from interpreting the functional effects of non-coding variants. We present CpGenie (http://cpgenie.csail.mit.edu), a deep convolutional neural network that learns a regulatory sequence code of DNA methylation and enables allele-specific DNA methylation prediction with single-nucleotide sensitivity. Variant annotations from CpGenie accurately identify methylation quantitative trait loci (meQTL) and contribute to the prioritization of functional non-coding variants including expression quantitative trait loci (eQTL) and disease-associated mutations.

Genomics

Accurate eQTL prioritization with an ensemble-based framework

Expression quantitative trait loci (eQTL) analysis links sequence variants with gene expression change and serves as a successful approach to fine-map variants causal for complex traits and understand their pathogenesis. In this work, we present an ensemble-based computational framework, EnsembleExpr, for eQTL prioritization. When trained on data from massively parallel reporter assays (MPRA), EnsembleExpr accurately predicts reporter expression levels from DNA sequence and identifies sequence variants that exhibit significant allele-specific reporter expression. This framework achieved the best performance in the \"eQTL-causal SNPs\" open challenge in the Fourth Critical Assessment of Genome Interpretation (CAGI 4). We envision EnsembleExpr to be a powerful resource for interpreting non-coding regulatory variants and prioritizing disease-associated mutations for downstream validation.

Genomics

Abundant contribution of short tandem repeats to gene expression variation in humans

Expression quantitative trait loci (eQTLs) are a key tool to dissect cellular processes mediating complex diseases. However, little is known about the role of repetitive elements as eQTLs. We report a genome-wide survey of the contribution of Short Tandem Repeats (STRs), one of the most polymorphic and abundant repeat classes, to gene expression in humans. Our survey identified 2,060 significant expression STRs (eSTRs). These eSTRs were replicable in orthogonal populations and expression assays. We used variance partitioning to disentangle the contribution of eSTRs from linked SNPs and indels and found that eSTRs contribute 10%-15% of the cis-heritability mediated by all common variants. Functional genomic analyses showed that eSTRs are enriched in conserved regions, co-localize with regulatory elements, and are predicted to modulate histone modifications. Our results show that eSTRs provide a novel set of regulatory variants and highlight the contribution of repeats to the genetic architecture of quantitative human traits.

Genomics

Whole Genome Regulatory Variant Evaluation for Transcription Factor Binding

The majority of disease-associated variants identified in genome-wide association studies (GWAS) reside in noncoding regions of the genome with regulatory roles. Thus being able to interpret the functional consequence of a variant is essential for identifying causal variants in the analysis of GWAS studies. We present GERV (Generative Evaluation of Regulatory Variants), a novel computational method for predicting regulatory variants that affect transcription factor binding. GERV learns a k-mer based generative model of transcription factor binding from ChIP-seq and DNase-seq data, and scores variants by computing the change of predicted ChIP-seq reads between the reference and alternate allele. The k-mers learned by GERV capture more sequence determinants of transcription factor binding than a motif-based approach alone, including both a transcription factors canonical motif as well as associated co-factor motifs. We show that GERV outperforms existing methods in predicting SNPs associated with allele-specific binding. GERV correctly predicts a validated causal variant among linked SNPs, and prioritizes the variants previously reported to modulate the binding of FOXA1 in breast cancer cell lines. Thus, GERV provides a powerful approach for functionally an-notating and prioritizing causal variants for experimental follow-up analysis. The implementation of GERV and related data are available at http://gerv.csail.mit.edu/

Bioinformatics