The MEGA format easily can designate genes and domains within the molecular sequence data. In this format, attributes of different sites (and groups of sites, termed domains) are specified within the data on the spot rather than in an attributes block before or after the actual data, as is the case in some other data formats. An example of a three-sequence dataset written in MEGA format is shown below. The sequences consist of three genes named FirstGene, SecondGene, and ThirdGene for two groups of organisms Setup/Select Genes/Domain (Mammals and Birds). (Note that the genes and domains can also be defined interactively through a dialog box.)!Gene=FirstGene Domain=Exon1 Property=Coding;
#Human_{Mammal} ATGGTTTCTAGTCAGGTCACCATGATAGGTCTCAAT
#Mouse_{Mammal} ATGGTTTCTAGTCAGGTCACCATGATAGGTCCCAAT
#Chicken_{Aves} ATGGTTTCTAGTCAGCTCACCATGATAGGTCTCAAT
!Gene=SecondGene Domain=Intron Property=Noncoding;
#Human ATTCCCAGGGAATTCCCGGGGGGTTTAAGGCCCCTTTAAAGAAAGAT
#Mouse GTAGCGCGCGTCGTCAGAGCTCCCAAGGGTAGCAGTCACAGAAAGAT
#Chicken GTAAAAAAAAAAGTCAGAGCTCCCCCCAATATATATCACAGAAAGAT
!Gene=ThirdGene Domain=Exon2 Property=Coding;
#Human ATCTGCTCTCGAGTACTGATACAAATGACTTCTGCGTACAACTGA
#Mouse ATCTGATCTCGTGTGCTGGTACGAATGATTTCTGCGTTCAACTGA
#Chicken ATCTGCTCTCGAGTACTGCTACCAATGACTTCTGCGTACAACTGA