This stoichiometry is in agreement with data by Esposito et al.,43 who also reported a ratio of 5 × CD95:5 × FADD together with some 6 × CD95:5 × FADD and 7 × CD95:5 × FADD ratios, but not the 4 × CD95:4 × FADD suggested by Scott et al. Disparities between these models could be explained by the different conditions used for protein crystallisation; however, the models proposed by Wang et al. and Esposito et al. are supported by the fact that they account for mutations frequently seen in autoimmune lymphoproliferative syndrome. The gene discussed is FAS; the disease is autoimmune lymphoproliferative syndrome.