TY - JOUR TI - Gene Networks Based on the Graphical Gaussian Model AU - Ma, Shisong VL - 2 IS - 4 PY - 2012 DA - 2012/02/20 SP - e119 C1 - Bio-protocol 2012;2:e119 DO - 10.21769/BioProtoc.119 UR - https://doi.org/10.21769/BioProtoc.119 AB - This protocol describes how to build a gene network based on the graphical Gaussian model (GGM) from large scale microarray data. GGM uses partial correlation coefficient (pcor) to infer co-expression relationship between genes. Compared to the traditional Pearson’ correlation coefficient, partial correlation is a better measurement of direct dependency between genes. However, to calculate pcor requires a large number of observations (microarray slides) greatly exceeding the number of variables (genes). This protocol uses a regularized method to circumvent this obstacle, and is capable of building a network for ~20,000 genes from ~2,000 microarray slides. For more details, see Ma et al. (2007). For help regarding the script, please contact the author. JF - Bio-protocol SN - 2331-8325 PB - Bio-protocol LLC. BIO101 - False