In serotypes AAV6 and AAV8, an acetylated VP3 variant commencing at A212 for AAV6 and A213 for AAV8 ((Ac)VP3 Variant) was also identified and confirmed with peptide mapping (AAV6: Table and Figure , AAV8: Table and Figure ). The presence of this variant in some AAV serotypes is the product of their VP3 DNA sequences containing a second ATG initiation codon at M211 (or M212 for AAV8) along with the more common ATG initiation codon at M203 (or M204 for AAV8) .