FasL is also produced by non-immune cells, such as Sertoli cells in the testis, corneal endothelium and epithelium of the eye, extravillous trophoblasts (EVT) at the implantation site and several types of tumour cells (Bellgrau et al, 1995; Suda et al, 1995; Griffith et al, 1996; Makrigiannakis et al, 2001; O'Connell et al, 2001). The gene discussed is FASLG; the disease is neoplasm.