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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) 
>NT_004668|FCGR2B*01|Homo sapiens|F|EX1
MGILSFLPVLATESDWADCKSPQPWGHMLLWTAVLFL
>M90729|FCGR2B*01|Homo sapiens|F|EX2
PVAGTP
>M90730|FCGR2B*01|Homo sapiens|F|EX3|D1|C-LIKE|
.....PAAPPKAVLKLEPQWINVLQ.EDSVTLTCRGTHSPE...SDSIQWFHNGNL....
.IPTHTQ..................PSYRFKANN...NDSGEYTCQTGQ...........
.......TSLSDPVHLTVLS
>M90731|FCGR2B*01|Homo sapiens|F|EX4|D2|C-LIKE|
..........WLVLQTPHLEFQE...GETIVLRCHSWKDKP...LVKVTFFQNGKSK...
.KFSRSD..................PNFSIPQANH..SHSGDYHCTGNIG..........
.....YTLYSSKPVTITVQA
>M90732|FCGR2B*01|Homo sapiens|F|EX5
PSSSPMGIIVAVVTGIAVAAIVAAVVALIYCRKKRIS
>M90733|FCGR2B*01|Homo sapiens|F|EX6
LPGYPECREMGETLPEKP
>M90734|FCGR2B*01|Homo sapiens|F|EX7
NPTNPDEADKVG
>M90735|FCGR2B*01|Homo sapiens|F|EX8
AENTITYSLLMHPDALEEPDDQNRI