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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) 
>AF394451|B7H3*01|Mus musculus|F|EX1|
atgcttcgaggatggggtggccccagtgtgggtgtgtgtgtgcgcacagcactgggggtg
ctgtgcctctgcctcacag
>AF394451|B7H3*01|Mus musculus|F|EX2|[D1]|V-LIKE|
gagctgtggaagtccaggtctctgaagaccccgtggtggccctggtggacacggatgcca
ccctacgctgctccttttccccagagcctggcttcagt...ctggcacagctcaacctca
tctggcagctgacagacaccaaacagctggtgcacagcttcacggagggc..........
..............cgggaccaaggcagtgcctactccaaccgcacagcgctcttccctg
acctgttggtgcaaggcaatgcgtccttgaggctgcagcgcgtccgagtaaccgacgagg
gcagctacacctgctttgtgagcatc...............caggactttgacagcgctg
ctgttagcctgcaggtggccg
>AF394451|B7H3*01|Mus musculus|F|EX3|[D2]|C-LIKE|
.ccccctactcgaagcccagcatgaccctggagcccaacaaggacctacgtccagggaac
atggtgaccatcacgtgctctagctaccagggctatccg.........gaggccgaggtg
ttctggaaggatggacagggagtgcccttgactggc...aatgtgaccacatcccagatg
gccaacgag.................................cggggcttgttcgatgtt
cacagcgtgctgagggtggtgctg.........ggtgctaacggcacctacagctgcctg
gtacgcaacccggtgttgcagcaagatgctcacggctcagtcaccatcacag
>AF394451|B7H3*01|Mus musculus|F|EX4|
ggcagcccctgacattcccccctgaggctctgtgggtaaccgtggggctctctgtctgtc
ttgtggtactactggtggccctggctttcgtgtgctggagaaagatcaagcagagctgcg
aggaggagaatgcag
>AF394451|B7H3*01|Mus musculus|F|EX5|
gtgccgaggaccaggatggagatggagaaggatccaagacag
>AF394451|B7H3*01|Mus musculus|F|EX6|
ctctacggcctctgaaaccctctgaaaacaaagaag
>AF394451|B7H3*01|Mus musculus|F|EX7|
atgacggacaagaaattgct