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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) 
>X67914|PDCD1*01|Mus musculus|F|EX1|
MWVRQVPWSFTWAVLQLSWQSGWLL
>X67914|PDCD1*01|Mus musculus|F|EX2|[D]|V-LIKE|
EVPNGPWRSLTFYPAWLTVSEGANATFTCSLSNWSE.....DLMLNWNRLSPSNQTEKQA
AFCN....GLSQPVQDA.....RFQIIQLPNRHDFHMNILDTRRNDSGIYLCGAISLH.P
KAKIEESPGAELVVT
>X67914|PDCD1*01|Mus musculus|F|EX3|
ERILETSTRYPSPSPKPEGRFQGMVIGIMSALVGIPVLLLLAWALAVFCSTSMS
>X67914|PDCD1*01|Mus musculus|F|EX4|
EARGAGSKDDTL
>X67914|PDCD1*01|Mus musculus|F|EX5|
KEEPSAAPVPSVAYEELDFQGREKTPELPTACVHTEYATIVFTEGLGASAMGRRGSADGL
QGPRPPRHEDGHCSWPL