Identification of Disease Critical Genes Using Collective Meta-heuristic Approaches: An Application to Preeclampsia. 
Identifying a small subset of disease critical genes out of a large size of microarray gene expression data is a challenge in computational life sciences.  This paper has applied four meta-heuristic algorithms, namely, honey bee mating optimization (HBMO), harmony search (HS), differential evolution (DE) and genetic algorithm (basic version GA) to find disease critical genes of preeclampsia which affects women during gestation.  Two hybrid algorithms, namely, HBMO-kNN and HS-kNN have been newly proposed here where kNN (k nearest neighbor classifier) is used for sample classification.  Performances of these new approaches have been compared with other two hybrid algorithms, namely, DE-kNN and SGA-kNN.  Three datasets of different sizes have been used.  In a dataset, the set of genes found common in the output of each algorithm is considered here as disease critical genes.  In different datasets, the percentage of classification or classification accuracy of meta-heuristic algorithms varied between 92.46 and 100%.  HBMO-kNN has the best performance (99.64-100%) in almost all data sets.  DE-kNN secures the second position (99.42-100%).  Disease critical genes obtained here match with clinically revealed preeclampsia genes to a large extent.