Identifying a small set of marker genes using minimum expected cost of misclassification

  • Authors:
  • Samuel H. Huang;Dengyao Mo;Jarek Meller;Michael Wagner

  • Affiliations:
  • School of Dynamic Systems, University of Cincinnati, 2600 Clifton Ave., Cincinnati, OH 45221, United States;School of Dynamic Systems, University of Cincinnati, 2600 Clifton Ave., Cincinnati, OH 45221, United States;Department of Environmental Health, University of Cincinnati, 2600 Clifton Ave., Cincinnati, OH 45267, United States;Division of Biomedical Informatics, Cincinnati Children's Hospital, 3333 Burnet Ave., Cincinnati, OH 45229, United States

  • Venue:
  • Artificial Intelligence in Medicine
  • Year:
  • 2012

Quantified Score

Hi-index 0.00

Visualization

Abstract

Objectives: This paper presents a model independent feature selection approach to identify a small subset of marker genes. Methods and material: An evaluation measure, minimum expected cost of misclassification (MEMC), is used to estimate the discriminative power of a feature subset without building a model. The MECM measure is combined with sequential forward search for feature selection. This approach was applied to a breast cancer profiling problem, with the goal of identifying a small number of marker genes whose expression can be used to predict cancer molecular subtype (p53 gene status). Furthermore, the method was also applied to find a small set of single-nucleotide polymorphisms (SNPs) that can be used to predict molecular phenotype of a different type, namely alleles (genetic variants) of human leukocyte antigen genes that play an important roles in autoimmunity. Results: Two marker genes were identified based on p53 status, which achieved a p-value of 7.53x10^-^5 (vs. 6x10^-^4 with 32 genes identified by previous research) in survival analysis. Six SNP loci were identified that achieved a leave-one-out cross-validation accuracy of 92.8% (vs. 90.6% and 89.5% with 18 SNPs selected using @g^2 statistics and information gain, respectively). Conclusion: The MECM-based feature selection approach is capable of identifying a smaller subset of market genes with comparable or even better performance than that obtained using conventional filter methods.