Refer figures 9-6 and 9-8:
The sequence of amino acids of a protein is decided by the triplet codons of the mRNA (messenger ribonucleic acid) and the amino acids are carried to the template by attaching to an adapter molecule by enzymes called aminoacyl-tRNA synthetases. The tRNA acts as adapter that brings the amino acid on to the ribosome. The sequence in anticodon loop of tRNA molecule is complementary to the codon for the amino acid carried by the tRNA. The codon in the mRNA and the anticodon in tRNA bind by particular complementary base pairing, as the codons in the mRNA are read in 5' to 3' direction and the anticodons are sloping and are composed in 3' to 5' direction.
The tRNA molecule generally exists as L-shaped folded clover leaf. The maintenance of the L-shape among the different tRNAs involves an important function. The formation of the L-shape would possibly impaired, when one of the bases in one of the stems get mutated, thus decreasing or removing the capacity of the tRNA to act as an adapter molecule.
When the tRNA gets mutated, it might not be able to attach with the synthetase molecule to turn into charged, or it might not form an enough stable complex with the ribosome during translation process. In any way, the mutant tRNA would not play a part in translation, but if inserted the mutant tRNA could interrupt the translation. In general, the result on the mutant organism would possibly negligible because there are number of copies of tRNA genes, and the regular function would be operated by the remaining normal copies of the gene.