Human body is bilaterally symmetric in appearance. However, internal organs exhibit obvious left-right asymmetry. Prof. Chikara Meno found that lefty genes are transiently expressed on the left side of mouse embryo. Lefty acts to another gene (Nodal) and restricts its expression only to the left side. This interaction creates proper left-right asymmetry. Recently, his group found that lefty1 is also involved in the anterior-posterior axis formation. He intends to advance the analysis of the axis formation and relate new findings to congenital anomalies and regenerative medicine.