Computational Biology and Bioinformatics


Genetical and Computational Genomics of Gene Networks

Sequential and contingent changes in gene expression strongly influence the development of organisms and their responses to the environment. These dynamic biological programs are executed via complex and still poorly defined networks of interactions among genes, transcripts, proteins, and numerous small molecules and cofactors. An adequate definition of these flexible and complex molecular circuits is an essential goal of functional genomics. High-throughput methods including transcriptome analysis and genome sequencing have generated huge amounts of data that can be exploited to systematically identify gene modulatory networks. A recent step forward in this direction involves merging complex trait analysis with transcriptome analysis. This genetical genomics approach treats normal variation in the expression of each gene as a quantitative trait. Quantitative trait locus (QTL) mapping methods are then used to identify the chromosomal intervals that harbor sequence variants (polymorphisms) that produce downstream variations in expression. We developed an integrated computational framework based on transcriptome QTL mapping, single nucleotide polymorphism (SNP) analysis and Bayesian network. Our method extends beyond mapping of regulatory loci to a systematic evaluation of possible gene modulatory relations using genome-wide genotype, SNP and gene expression data. (Reference)


Phenotypic Effects of Single Nucleotide Polymorphisms

There has been great expectation that knowledge of an individual’s genotype will provide a basis for assessing susceptibility to diseases and designing individualized therapy. About 90% of sequence variants in humans are differences in single bases of DNA, called single nucleotide polymorphisms. Nonsynonymous single nucleotide polymorphisms (nsSNP) that lead to an amino acid change in the protein product are of particular interest because they account for nearly half of the known genetic variations related to human inherited disease. To facilitate identifying disease-associated nsSNPs from neutral nsSNPs, we developed computational tools to predict the nsSNP’s phenotypic effect. (Reference)



Yan Cui's Lab at University of Tennessee Health Science Center