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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) 
>AF394451|B7H3*01|Mus musculus|F|EX1|
MLRGWGGPSVGVCVRTALGVLCLCLT
>AF394451|B7H3*01|Mus musculus|F|EX2|[D1]|V-LIKE|
GAVEVQVSEDPVVALVDTDATLRCSFSPEPGFS.LAQLNLIWQLTDTKQLVHSFTEG...
.....RDQGSAYSNRTALFPDLLVQGNASLRLQRVRVTDEGSYTCFVSI.....QDFDSA
AVSLQVA
>AF394451|B7H3*01|Mus musculus|F|EX3|[D2]|C-LIKE|
APYSKPSMTLEPNKDLRPGNMVTITCSSYQGYP...EAEVFWKDGQGVPLTG.NVTTSQM
ANE...........RGLFDVHSVLRVVL...GANGTYSCLVRNPVLQQDAHGSVTIT
>AF394451|B7H3*01|Mus musculus|F|EX4|
GQPLTFPPEALWVTVGLSVCLVVLLVALAFVCWRKIKQSCEEENA
>AF394451|B7H3*01|Mus musculus|F|EX5|
GAEDQDGDGEGSKT
>AF394451|B7H3*01|Mus musculus|F|EX6|
ALRPLKPSENKE
>AF394451|B7H3*01|Mus musculus|F|EX7|
DDGQEIA