Ablation experiment is an experiment designed to produce an animal deficient in one or the few cell types, in order to study cell lineage or the cell function. The logic is to make a transgenic mouse with a toxin gene (often known as diphtheria toxin) under control of a specialized promoter which activates only in the target cell type. When the embryo development progresses to the point where it starts to form the target tissue, the toxin gene is activated, and that particular tissue dies. Other tissues are not affected.