SAMD9L and ataxia-pancytopenia syndrome: Finally, we identified SAMD9L determinants of lentiviral inhibition and of cellular translational repression: (i) an essential SLFN-like box effector domain with key E198/D243 residues; and (ii) a C-terminal autoregulatory domain, previously identified in the context of SAAD/ATXPC patients [2].