A set of luminescence lines previously observed only in GaAs layers grown by molecular beam epitaxy (MBE) has been observed for the first time in layers grown by metalorganic vapor phase epitaxy (MOVPE). The lines which appear between 1.5515 and 1.504 eV are more evident in samples grown with low arsine concentrations and low substrate temperatures. It appears that these additional lines are due to recombinations involving native defects. Unlike the MBE case, extrinsic impurities from the reactants are incorporated in the layers during the growth, thus reducing the concentration of native defects responsible for the additional lines.