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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) 
>AF317088|B7H1*01|Mus musculus|F|EX1|
MRIFAGIIFTACCHLLR
>AF317088|B7H1*01|Mus musculus|F|EX2|[D1]|V-LIKE|
AFTITAPKDLYVVEYGSNVTMECRFPVERELD.LLALVVYWEKEDEQVIQFVAGEED...
...LKPQHSNFRGRASLPKDQLLKGNAALQITDVKLQDAGVYCCIISY.....GGADYKR
ITLKVN
>AF317088|B7H1*01|Mus musculus|F|EX3|[D2]|C-LIKE|
APYRKINQRISVDPA...TSEHELICQAE.GYP...EAEVIWTNSDHQPVS..GKRSVTT
SRT..........EGMLLNVTSSLRVNA.TANDVFYCTFWRSQ..PGQNHTAELIIPE
>AF317088|B7H1*01|Mus musculus|F|EX4|
ELPATHPPQNRTHWVLLGSILLFLIVVSTVLLFLRKQ
>AF317088|B7H1*01|Mus musculus|F|EX5|
VRMLDVEKCGVEDTSSKNRN
>AF317088|B7H1*01|Mus musculus|F|EX6|
DTQFEET
>AK154403|B7H1*02|Mus musculus|F|EX1|
MRIFAGIIFTACCHLLR
>AK154403|B7H1*02|Mus musculus|F|EX2|[D1]|V-LIKE|
AFTITAPKDLYVVEYGSNVTMECRFPVERELD.LLALVVYWEKEDEQVIQFVAGEED...
...LKPQHSNFRGRASLPKDQLLKGNAALQITDVKLQDAGVYCCIISY.....GGADYKR
ITLKVN
>AK154403|B7H1*02|Mus musculus|F|EX3|[D2]|C-LIKE|
APYRKINQRISVDPA...TSEHELICQAE.GYP...EAEVIWTNSDHQPVS..GKRSVTT
SRT..........EGMLLNVTSSLRVNA.TANDVFYCTFWRSQ..PGQNHTAELIIPE
>AK154403|B7H1*02|Mus musculus|F|EX4|
ELPATHPPQNRTHWVLLGSILLFLIVVSTVLLFLRKQ
>AK154403|B7H1*02|Mus musculus|F|EX5|
VRMLDVEKCGVEDTSSKNRN
>AK154403|B7H1*02|Mus musculus|F|EX6|
DTQFEET