The macromolecule RNA is common

English as a Second Language English Vocabulary, Grammar and Idioms
1
  1. The macromolecule RNA is common to all living beings, and DNA, which is found in all organisms except some bacteria, is almost as ubiquitous.
  2. The macromolecule RNA is common to all living beings, and DNA, which is found in all organisms except some bacteria, is almost ubiquitous.

Do the two sentences mean same?

2

No.
Only the first is correct to indicate that DNA is almost as prevalent as RNA.

The second sentence does not relate RNA to DNA at all. The two are treated completely separately and are not compared.