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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) 
>L12585|B7A1*01|Mus musculus|F|EX1|[D1]|V-LIKE|
MACNCQLMQDTPLLKFPCPRLILLFVLLIRLSQVSS
>L12586|B7A1*01|Mus musculus|F|EX2|[D1]|V-LIKE|
DVDEQLSKSVKDKVLLPCRYNSPHED..ESEDRIYWQKH....DKVVLSVIA......GK
LKVWPEYK..NRTLYDNT..TYSLIILGLVLSDRGTYSCVVQKKERGTYEVKHLALVKLS
IK
>L12587|B7A1*01|Mus musculus|F|EX3|[D2]|C-LIKE|
........ADFSTPNITESGNPS...ADTKRITCFASGGFP...KPRFSWLENGRELPGI
.NTTISQDPE............SELYTISSQLDFNT.TRNHTIKCLIKYG....DAHVSE
DFTWEK
>L12588|B7A1*01|Mus musculus|F|EX4|
PPEDPPDSKNTLVLFGAGFGAVITVVVIVVIIKCFCKH
>L12589|B7A1*01|Mus musculus|F|EX5|
NLQGSCFRRNEASRETNNSLTFGPEEALAEQTVFL
>AF065894|B7A1*02|Mus musculus|F|EX1|[D1]|V-LIKE|Splicing B|
MACNCQLMQDTPLLKFPCPRLILLFVLLIRLSQVSS
>AF065894|B7A1*02|Mus musculus|F|EX2|[D1]|V-LIKE|Splicing B|
DVDEQLSKSVKDKVLLPCRYNSPHED..ESEDRIYWQKH....DKVVLSVIA......GK
LKVWPEYK..NRTLYDNT..TYSLIILGLVLSDRGTYSCVVQKKERGTYEVKHLALVKLS
IK
>AF065894|B7A1*02|Mus musculus|F|EX3|[D2]|C-LIKE|Splicing B|
........ADFSTPNITESGNPS...AGTKRITCFASGGFP...KPRFSWLENGRELPGI
.NTTISQDPE............SELYTISSQLDFNT.TRNHTIKCLIKYG....DAHVSE
DFTWEK
>AF065894|B7A1*02|Mus musculus|F|EX4|Splicing B|
PPEDPPDSKNTLVLFGAGFGAVITVVVIVVIIKCFCKH
>AF065894|B7A1*02|Mus musculus|F|EX5|Splicing B|
RSCFRRNEASRETNNSLTFGPEEALAEQTVFL
>D16220|B7A1*03|Mus musculus|F|EX1|[D1]|V-LIKE|Splicing C|
MACNCQLMQDTPLLKFPCPRLILLFVLLIRLSQVSS
>D16220|B7A1*03|Mus musculus|F|EX2|[D1]|V-LIKE|Splicing C|
DVDEQLSKSVKDKVLLPCRYNSPHED..ESEDRIYWQKH....DKVVLSVIA......GK
LKVWPEYK..NRTLYDNT..TYSLIILGLVLSDRGTYSCVVQKKERGTYEVKHLALVKLS
IK
>D16220|B7A1*03|Mus musculus|F|EX4|Splicing C|
APEDPPDSKNTLVLFGAGFGAVITVVVIVVIIKCFCKH
>D16220|B7A1*03|Mus musculus|F|EX5|Splicing C|
RSCFRRNEASRETNNSLTFGPEEALAEQTVFL