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IMGT reference sequences in FASTA format:

Amino acid sequences without 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
RTPKIQVYSRHPAENGKSNFLNCYVSGFHPSDIEVDLLKNGERIEKVEHSDLSFSKDWSF
YLLYYTEFTPTEKDEYACRVNHVTLSQPKIVKW
>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
IQRTPKIQVYSRHPAENGKSNFLNCYVSGFHPSDIEVDLLKNGERIEKVEHSDLSFSKDW
SFYLLYYTEFTPTEKDEYACRVNHVTLSQPKIVKWDRDM
>AB021288|B2M*01|Homo sapiens|F
MSRSVALAVLALLSLSGLEAIQRTPKIQVYSRHPAENGKSNFLNCYVSGFHPSDIEVDLL
KNGERIEKVEHSDLSFSKDWSFYLLYYTEFTPTEKDEYACRVNHVTLSQPKIVKWDRDM