Off topic:find pattern in vi

Question

[rockfrancis]

I need to find patterns in the following sequence: GGAGTTCTACCGCAGGGGCGGGGAACTCCAAGTGATATCCATCATCGCATCCAGTGCGTCCGGTTTATCC TCGCTGACGCGGGGAACTCTTGGTTGTTCGGCGTTTTGAAGAGAACAAAAACGGTTTATCCCCGCTGGCG CGGGGAACTCGACTCAATGGCAACCGTCACGGCCTGTCCTGGCGGTTTATCCCCGCTGGCGCGGGAAC CGCGGTCGATTTTGCTGGCGTTGTTTCGGCTGGCGGTTTATCCCCGCTGGCGCGGGGAACTCTGCATAAA

I have this line :%s/ATG(.{3}){- 1.}(TAA|TAG|TGA)//g but it is incorrect.