DEPARTMENT OF STATISTICS
Statistics Colloquium
University of Connecticut
Storrs, Connecticut
The Department of Statistics Cordially invites you to a Colloquium
Professor Hongyu Zhao
Ira V. Hiscock Professor of Public Health (Biostatistics) and Professor of Genetics and of Statistics
Yale University
Spatial Temporal Modeling of Gene Expression Networks
During Human Brain Development
ABSTRACT
Human neurodevelopment is a highly regulated biological process, and recent technological advances allow scientists to study the dynamic changes of neurodevelopment at the molecular level through the analysis of gene expression data from human brains. In this talk, we focus on the analysis of data sampled from 16 brain regions in 15 time periods of neurodevelopment. Our aim is to infer region and time-specific co-expression networks. The network is characterized by Gaussian Graphical Models (GGM). We will introduce a Bayesian neighborhood selection procedure to estimate the graph structure. The procedure is extended to a jointly modeling framework. Markov Random Field (MRF) models are used to efficiently utilize the information embedded in the brain region and temporal similarity, where the degrees of similarity are learnt adaptively from the data. We have also developed and implemented an efficient algorithm that enables parallel computing. Simulation studies suggest that our approach achieves better accuracy in network estimation compared with models not incorporating spatial and temporal dependency. In the extreme case that there is no more similarity shared than random graphs, our joint estimation approach achieves comparable performance with methods that estimate the graphs independently. Some theoretical properties of the procedure will be briefly discussed. We will also describe our methods to infer differentially expressed genes from these data. This is joint work with Zhixiang Lin, Stephan Sanders, Mingfeng Li, Nenad Sestan, and Matthew State.
DATE: Wednesday, January 21, 2015
TIME: 4:00 p.m.
PLACE: Philip E. Austin Building – Room 105
Coffee will be served at 3:30 in room 326
For more information, contact: Tracy Burke at tracy.burke@uconn.edu