Joint Identification of Multiple Genetic Variants of Obesity in a Korean Genome-wide Association Study

In recent years, genome-wide association (GWA) studies have successfully led to many discoveries of genetic variants affecting common complex traits, including height, blood pressure, and diabetes. Although GWA studies have made much progress in finding single nucleotide polymorphisms (SNPs) associated with many complex traits, such SNPs have been shown to explain only a very small proportion of the underlying genetic variance of complex traits. This is partly due to that fact that most current GWA studies have relied on single-marker approaches that identify single genetic factors individually and have limitations in considering the joint effects of multiple genetic factors on complex traits. Joint identification of multiple genetic factors would be more powerful and provide a better prediction of complex traits, since it utilizes combined information across variants. Recently, a new statistical method for joint identification of genetic variants for common complex traits via the elastic-net regularization method was proposed. In this study, we applied this joint identification approach to a large-scale GWA dataset (i.e., 8842 samples and 327,872 SNPs) in order to identify genetic variants of obesity for the Korean population. In addition, in order to test for the biological significance of the jointly identified SNPs, gene ontology and pathway enrichment analyses were further conducted.

Study of Linear Sampling Method with Partial-view Data in Electromagnetic Inverse Scattering Imaging / 航天医学与医学工程

Objective To study the application of the linear sampling method(LSM) in 2D electromagnetic inverse scattering imaging and to mainly discuss the imaging quality of LSM with partial-view data.Methods Get the norm of solution vector to the equivalent integral equation using numerical calculation in every sampling point at imaging region,and represent the norm with gray to reconstruct the scattering shape.Results Under all incident angles [0,360?] and all observation angles [0,360?],the imaging quality of the far-field pattern of scattering wave was obtained very well.But when reducing the range of the incident angles and observation angles,the imaging quality declined.Particularly,the imaging quality in the case of both incident angles and observation angles being at the same side of the observed object,were much better than both in opposite sides.Furthermore,the profile of the object was imaged more clearly as its position corresponding to the orientation of the incident/observation angle.Conclusion Although the imaging quality will decline with partial-view data in electromagnetic inverse scattering,the effectiveness of imaging with LSM still deserves attention.