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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) 
>L27587|CD79B*01|Homo sapiens|F|EX1|
MARLALSPVPSHWMVALLLLLS
>L27587|CD79B*01|Homo sapiens|F|EX2|
AEPVPAARSEDRYRNPK
>L27587|CD79B*01|Homo sapiens|F|EX3|[D]|C-LIKE|
GSACSRIWQSPRFIARKRGFTVKMHCYMNSASGNVSWLWKQEMDENPQQLKLEKGRMEES
QNESLATLTIQGIRFEDNGIYFCQQKCNNTSEVYQGCGTELRVM
>L27587|CD79B*01|Homo sapiens|F|EX4|
GFSTLAQLKQRNTLKDGIIMIQTLLIILFIIVPIFLLLDK
>L27587|CD79B*01|Homo sapiens|F|EX5|
DDSKAGMEEDHTYE
>L27587|CD79B*01|Homo sapiens|F|EX6|
GLDIDQTATYEDIVTLRTGEVKWSVGEHPGQE
>CD79B*01|Homo sapiens|F|EX1-6|Complete|Splicing A|
MARLALSPVPSHWMVALLLLLSAEPVPAARSEDRYRNPKGSACSRIWQSPRFIARKRGFT
VKMHCYMNSASGNVSWLWKQEMDENPQQLKLEKGRMEESQNESLATLTIQGIRFEDNGIY
FCQQKCNNTSEVYQGCGTELRVMGFSTLAQLKQRNTLKDGIIMIQTLLIILFIIVPIFLL
LDKDDSKAGMEEDHTYEGLDIDQTATYEDIVTLRTGEVKWSVGEHPGQE*