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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) 
>AB021288|B2M*01|Homo sapiens|F|EX1
.....MSRSVALAVLALLSLSGLEAIQ
>AB021288|B2M*01|Homo sapiens|F|EX2
RTPKIQVYSRHPAEN....GKSNFLNCYVSGFHP..SDIEVDLLKNGERIE...KVEHSD
LSFSKD......WSFYLLYYTEFTP.....TEKDEYACRVNHVT..............LS
QPKIVKW
>AB021288|B2M*01|Homo sapiens|F|EX3
DRDM
>AB021288|B2M*01|Homo sapiens|F|L-REGION
.....MSRSVALAVLALLSLSGLEA
>AB021288|B2M*01|Homo sapiens|F|[D]|C-LIKE-DOMAIN
IQRTPKIQVYSRHPAEN....GKSNFLNCYVSGFHP..SDIEVDLLKNGERIE...KVEH
SDLSFSKD......WSFYLLYYTEFTP.....TEKDEYACRVNHVT..............
LSQPKIVKWDRDM
>AB021288|B2M*01|Homo sapiens|F
.....MSRSVALAVLALLSLSGLEAIQRTPKIQVYSRHPAEN....GKSNFLNCYVSGFH
P..SDIEVDLLKNGERIE...KVEHSDLSFSKD......WSFYLLYYTEFTP.....TEK
DEYACRVNHVT..............LSQPKIVKWDRDM