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IMGT reference sequences in FASTA format:

Amino acid sequences with gaps

The FASTA header contains:
IMGT accession number | gene and allele name | species | functionality | exon name | domain name | domain type | alternative splicing (if it is) | partial (if it is) 
>AF142780|B7DC*01|Mus musculus|F|EX1|
MLLLLPILNLSLQLHPVA
>AF142780|B7DC*01|Mus musculus|F|EX2|[D1]|V-LIKE|
ALFTVTAPKEVYTVDVGSSVSLECDFDRRECTE.LEGIRASLQ..........KVE....
......NDTSLQSERATLLEEQLPLGKALFHIPSVQVRDSGQYRCLVICG.....AAWDY
KYLTVKVK
>AF142780|B7DC*01|Mus musculus|F|EX3|[D2]|C-LIKE|
ASYMRIDTRILEVPG...TGEVQLTCQAR.GYP...LAEVSWQNVSVPAN...TSHIRTP
E..............GLYQVTSVLRLKP.QPSRNFSCMFW.......NAHMKELTSAIID
PL
>AF142780|B7DC*01|Mus musculus|F|EX4|
SRMEPKVPRTWPLHVFIPACTIALIFLAIVIIQRKRI