Objectives The objectives of this project are to confirm the gene profiled from comparing normal and OSA patients as well as OSA patients before and after CPAP treatment, to investigate the correlation between altered gene expression and clinical presentations and CPAP effects of the OSAS and to identify and confirm corresponding pathway. This study will enhance our understanding of the individual constitution on widely different clinical characteristics and therapeutic variations. All these efforts will also help us to interpret its molecular mechanisms and develop prediction and diagnosis strategies of OSAS. The long-term objectives are to develop therapeutic strategy other than CPAP of OSAS.