Here you are: IMGT Web resources > IMGT Repertoire (RPI) > RPI entries from gene to protein

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) 
>M91646|FCGR1B*01|Homo sapiens|F|EX1|
MWFLTTLLLW
>M91646|FCGR1B*01|Homo sapiens|F|EX2|
PVDGQV
>M91646|FCGR1B*01|Homo sapiens|F|EX3|[D1]|C-LIKE|
........TTKAVITLQPPWVSVFQ.EETVTLHCEVLHLPG...SSSTQWFLNGTA....
.TQTST...................PSYRITSASV..NDSGEYRCQRGL...........
.......SGRSDPIQLEIHR
>M91646|FCGR1B*01|Homo sapiens|F|EX4|[D2]|C-LIKE|
..........WLLLQVSSRVFME...GEPLALRCHAWKDKL...VYNVLYYRNGKAF...
.KFFHWN..................SNLTILKTNI..SHNGTYHCSGMGK..........
......HRYTSAGISQYTVK
>M91646|FCGR1B*01|Homo sapiens|F|EX5|[D3]|C-LIKE|
...LFPAPVLNASVTSPLLEG......NLVTLSCETKLLLQ..RPGLQL*
>L03419|FCGR1B*01|Homo sapiens|F|EX1|splicingB
MWFLTTLLLW
>L03419|FCGR1B*01|Homo sapiens|F|EX2|splicingB
PVDGQV
>L03419|FCGR1B*01|Homo sapiens|F|EX3|[D1]|C-LIKE|splicingB
........TTKAVITLQPPWVSVFQ.EETVTLHCEVLHLPG...SSSTQWFLNGTA....
.TQTST...................PSYRITSASV..NDSGEYRCQRGL...........
.......SGRSDPIQLEIHR
>L03419|FCGR1B*01|Homo sapiens|F|EX4|[D2]|C-LIKE|splicingB
..........WLLLQVSSRVFME...GEPLALRCHAWKDKL...VYNVLYYRNGKAF...
.KFFHWN..................SNLTILKTNI..SHNGTYHCSGMGK..........
......HRYTSAGISQYTVK
>L03419|FCGR1B*01|Homo sapiens|F|EX6|[D4]|splicingB
LQLPTPVWFHVLFYLAVGIMFLVNTVLWVTIRKELKRKKKWNLEISLDSGHEKKVISSLQ
EDRHLEEELKCQEQKEEQLQEGVHRKEPQGAT*
>L03420|FCGR1B*02|Homo sapiens|F|EX1|splicingC
MWFLTTLLLW
>L03420|FCGR1B*02|Homo sapiens|F|EX4|[D2]|C-LIKE|splicingC
..........WLLLQVSSRVFME...GEPLALRCHAWKDKL...VYNVLYYRNGKAF...
.KFFHWN..................SNLAILKTNI..SHNGTYHCSGMGK..........
......HRYTSAGISQYTVK
>L03420|FCGR1B*02|Homo sapiens|F|EX6|[D4]|splicingC
LQLPTPVWFHVLFYLAVGIMFLVNTVLWVTIRKELKRKKKWNLEISLDSGHEKKVISSLQ
EDRHLEEELKCQEQKEEQLQEGVHRKEPQGAT*