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IMGT reference sequences in FASTA format:

Nucleotide 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) 
>AF142780|B7DC*01|Mus musculus|F|EX1|
atgctgctcctgctgccgatactgaacctgagcttacaacttcatcctgtagcag
>AF142780|B7DC*01|Mus musculus|F|EX2|[D1]|V-LIKE|
.ctttattcaccgtgacagcccctaaagaagtgtacaccgtagacgtcggcagcagtgtg
agcctggagtgcgattttgaccgcagagaatgcactgaa...ctggaagggataagagcc
agtttgcag..............................aaggtagaa............
..................aatgatacgtctctgcaaagtgaaagagccaccctgctggag
gagcagctgcccctgggaaaggctttgttccacatccctagtgtccaagtgagagattcc
gggcagtaccgttgcctggtcatctgcggg...............gccgcctgggactac
aagtacctgacggtgaaagtcaaag
>AF142780|B7DC*01|Mus musculus|F|EX3|[D2]|C-LIKE|
.cttcttacatgaggatagacactaggatcctggaggttccaggt.........acaggg
gaggtgcagcttacctgccaggctaga...ggttatccc.........ctagcagaagtg
tcctggcaaaatgtcagtgttcctgccaac.........accagccacatcaggaccccc
gaa..........................................ggcctctaccaggtc
accagtgttctgcgcctcaagcct...cagcctagcagaaacttcagctgcatgttctgg
.....................aatgctcacatgaaggagctgacttcagccatcattgac
cctctga
>AF142780|B7DC*01|Mus musculus|F|EX4|
gtcggatggaacccaaagtccccagaacgtggccacttcatgttttcatcccggcctgca
ccatcgctttgatcttcctggccatagtgataatccagagaaagaggatc