Schematic diagram of the locations of germline mutations and potential revertants with respect to the predicted domains of SAMD9 (NM_017654) and SAMD9L (NM_152703) proteins based on Mekhedov et al. (12). Germline mutations (top) and potential revertants (bottom) are shown. Mutations and revertants are color coded for each family (1: green, 2: orange, 3: purple, 4: blue, 5: red). SAM, sterile α motif domain; AlbA, acetylation lowers binding affinity; DNA-binding domain; PPR, pentatricopeptide repeat; SIR2, silent mating–type information regulation 2; P-loop NTPase, P-loop–containing nucleoside triphosphate hydrolase; TPR, tetratricopeptide repeat–containing domain; OB, oligonucleotide/oligosaccharide–binding fold domain. Figure not drawn to scale.