The study demonstrates that with a proper modification feature selection algorithms can be tailored for imbalanced data sampling. In addition to being self-adaptable to different datasets, the proposed hybrid system is quite flexible, allowing different classifiers and evaluation components to be easily integrated for any specific problem at hand. The imbalanced data sampling problem is ubiquitous in clinical and medical diagnoses as well as gene function predication and protein classification. The proposed hybrid system can not only recover the power of classifiers on imbalance data classification but also indicate the relative importance of samples from majority class in contrast to samples from minority class. This information could be used for further biological and medical investigations which may result in the discovery of new conditions or disease subtypes. We anticipate that such a hybrid formulation can provide a new means for tackling imbalanced data problems introduced in these applications.