Scientists at CIMMYT have developed and adapted a transformation technique for wheat and maize to produce genetically modified plants that do not carry the selectable marker genes. With this technique, two DNA fragments, one containing the selectable marker gene and the other containing the gene of interest, are introduced and integrated separately into the genome. During the selection process, these genes segregate from each other, allowing the selection of the plants with only the gene of interest. CIMMYT scientists tested this simple technique using the selectable gene bar and the Bt genes, Cry1Ab and Cry1Ba, and successfully obtained plants without the selectable marker gene but with the Bt gene and which expressed high levels of Bt toxin. Transgenic plants were morphologically indistinguishable from untransformed plants and the introduced trait was inherited stably in the subsequent generations.