Researchers have developed a synthetic form of DNA with 6 di

Researchers have developed a synthetic form of DNA with 6 different bases A, T, C, G, and two additional novel bases X and Y. These novel bases form stable X-Y pairs during in vitro DNA replication, and are not excised by DNA repair pathways. The resulting bacterium is the first organism to stably propagate an expanded range of DNA bases (Malyshev, et al. Nature, doi: 10:1038/nature1 3314). Now that we know that a DNA molecule with six different nucleotides is possible, provide a brief well reasoned discussion of what the genetic code might look like for such an organism if it had evolved naturally. The following three amino acid sequences are all based on a homologous coding region of DNA in which different point mutations have occurred Based on the three amino acid sequences derive the composition and order of the nucleotides in the 3 DNA sequences.

Solution

Answer:-Normally genetic code is triplet consists of three nucleotides or bases. However if the organism contains six nitrogenous bases instead of four the the possible codons would be same as all twenty aminoacids would be coded in polypeptide.