"The RNA world hypothesis
is extremely unlikely," said Carter.
(9) According to the RNA World Hypothesis
, the first living system was a polymer(s) of catalytic RNA capable of self-replication that subsequently evolved the ability to encode more versatile peptide catalysts.
To support the RNA world hypothesis
, numerous artificial RNA enzymes (ribozymes) have been isolated by the powerful combinatorial technique called SELEX.
Among the most challenging questions for the RNA world hypothesis
is, What would have been the source of the RNA nucleotides?