 However, there are some limitations in chloroplast DNA manipulation, such as the inability to manipulate cereal crop DNA material and poor expression of foreign DNA in non- green plastids as mentioned before.In addition, the lack of post- translational modification capability like glycosylation in plastids may make some human- related protein expression difficult.Nevertheless, much progress has been made into plant transplastomics, for example, the production of edible vaccines for Tetanus by using a transplastomic tobacco plant.