To provide an improved method for the somatic gene therapy using enhanced gene transfer, a colony and a new construction for enhancing the DNA transfer into a cell by retrovirus mediation, and the use thereof.

The method for increasing the transduction efficiency of a hemopoietic cell and other cells by retrovirus includes the infection of the cell in the presence of fibronectin or fibronectin fragment. It is clear from the figs. (refer to the specification), the fibronectin or the fibronectin fragment significantly enhances the retrovirus-mediated gene transfer to a cell, especially hematopoietic cell including committed progenitor and primitive hematopoietic stem cell.