It is known that the loss of 2-thiolation of τm5s2U is strongly associated with the development of reversible infantile liver failure (RILF) because pathogenic mutations of RILF were found in the MTU1 gene, which encodes an enzyme responsible for the 2-thiolation of τm5s2U. However, the molecular mechanism underlying RILF pathogenesis associated with a lack of MTU1 remains elusive. This evidence concerns the gene TRMU and infantile liver failure.