- The Drosophila melanogaster DNA Ligase IV gene plays a crucial role in the repair of radiation-induced DNA double-strand breaks and acts synergistically with Rad54. Gorski, M.M., Eeken, J.C., de Jong, A.W., Klink, I., Loos, M., Romeijn, R.J., van Veen, B.L., Mullenders, L.H., Ferro, W., Pastink, A. Genetics (2003)