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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) 
>J04162|FCGR3B*01|Homo sapiens|F|EX1
MWQLLLPTALLLL
>J04162|FCGR3B*01|Homo sapiens|F|EX2
VSAGMRT
>J04162|FCGR3B*01|Homo sapiens|F|EX3|D1|C-LIKE|
......EDLPKAVVFLEPQWYRVLE.KDSVTLKCQGAYSPE...DNSTQWFHNENL....
.ISSQA.....SSYFIDAATVDDSGEYRCQTNL......STLSDPVQLEVHV
>J04162|FCGR3B*01|Homo sapiens|F|EX4|D2|C-LIKE|
.........GWLLLQAPRWVFKE...EDPIHLRCHSWKNTA...LHKVTYLQNGKDR...
.KYFHHN....SDFHIPKATLKDSGSYFCRGLVG...SKNVSSETVNITITQ
>J04162|FCGR3B*01|Homo sapiens|F|EX5
GLAVSTISSFSPPGYQVSFCLVMVLLFAVDTGLYFSVKTNI*
>FCGR3B*01|Homo sapiens|F|
MWQLLLPTALLLLVSAGMRTEDLPKAVVFLEPQWYRVLEKDSVTLKCQGAYSPEDNSTQW
FHNENLISSQASSYFIDAATVDDSGEYRCQTNLSTLSDPVQLEVHVGWLLLQAPRWVFKE
EDPIHLRCHSWKNTALHKVTYLQNGKDRKYFHHNSDFHIPKATLKDSGSYFCRGLVGSKN
VSSETVNITITQGLAVSTISSFSPPGYQVSFCLVMVLLFAVDTGLYFSVKTNI*