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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) 
>AY322147|B7H4*01|Mus musculus|F|EX1|
MASLGQIIFWS
>AY322147|B7H4*01|Mus musculus|F|EX2|
IINIIIILAGAIALIIGFGIS
>AY322147|B7H4*01|Mus musculus|F|EX3|[D1]|V-LIKE|
GKHFITVTTFTSAGNIGEDGTLSCTFEPDIKL...NGIVIQWLKEGIKGLVHEFKEGKD.
...DLSQQHEMFRGRTAVFADQVVVGNASLRLKNVQLTDAGTYTCYIRTS....KGKGNA
NLEYKTG
>AY322147|B7H4*01|Mus musculus|F|EX4|[D2]|C-LIKE|
AFSMPEINVDYNAS......SESLRCEAPRWFP...QPTVAWASQVDQGANFSEVSNTSF
ELNS.........ENVTMKVVSVLYNV..TINNTYSCMIENDIAKATGDIKVT
>AY322147|B7H4*01|Mus musculus|F|EX5|
DSEVKRRSQLQLLNSGPSPCVFSSAFAAGWALLSLSCCLMLR
>AK143276|B7H4*02|Mus musculus|F|EX1|
MASLGQIIFWS
>AK143276|B7H4*02|Mus musculus|F|EX2|
IINIIIILAGAIALIIGFGIS
>AK143276|B7H4*02|Mus musculus|F|EX3|[D1]|V-LIKE|
GKHFITVTTFTSAGNIGEDGTLSCTFEPDIKL...NGIVIQWLKEGIKGLVHEFKEGKD.
...DLSQQHEMFRGRTAVFADQVVVGNASLRLKNVQLTDAGTYTCYIRTS....KGKGNA
NLEYKTG
>AK143276|B7H4*02|Mus musculus|F|EX4|[D2]|C-LIKE|
AFSMPEINVDYNAS......SESLRCEAPRWFP...QPTVAWASQVDQGANFSEVSNTSF
ELNS.........ENVTMKVVSVLYNV..TINNTYSCMIENDIAKATGDIKVT
>AK143276|B7H4*02|Mus musculus|F|EX5|
DSEVKRRSQLQLLNSGPSPCVFSSAFVAGWALLSLSCCLMLR
>BC032925|B7H4*03|Mus musculus|F|EX1|
MASLGQIIFWS
>BC032925|B7H4*03|Mus musculus|F|EX2|
IINIIIILAGAIALIIGFGIS
>BC032925|B7H4*03|Mus musculus|F|EX3|[D1]|V-LIKE|
GKHFITVTTFTSAGNIGEDGTLSCTFEPDIKL...NGIVIQWLKEGIKGLVHEFKEGKD.
...DLSQQHEMFRGRTAVFADQVVVGNASLRLKNVQLTDAGTYTCYIRSS....KGKGNA
NLEYKTG
>BC032925|B7H4*03|Mus musculus|F|EX4|[D2]|C-LIKE|
AFSMPEINVDYNAS......SESLRCEAPRWFP...QPTVAWASQVDQGANFSEVSNTSF
ELNS.........ENVTMKVVSVLYNV..TINNTYSCMIENDIAKATGDIKVT
>BC032925|B7H4*03|Mus musculus|F|EX5|
DSEVKRRSQLQLLNSGPSPCVSSSAFVAGWALLSLSCCLMLR