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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) 
>M13733|CD79A*01|Mus musculus|F|EX1|
atgccagggggtctagaagccctcagagccctgcctctcctcctcttcttgtcatacgcc
tgtttgg
>M13733|CD79A*01|Mus musculus|F|EX2|[D1]|C-LIKE|
Gtcccggatgccaggccctgcgggtagaagggggtccaccatccctgacggtgaacttg.
........ggcgaggaggcccgcctcacctgtgaaaacaatggcaggaac..........
.....cctaatatcacatggtggttcagccttcagtct...............aacatca
catggcccccagtgccactgggtcct........................ggccagggta
ccacaggccagctgttcttccccgaagtaaacaag......aacacaggggcttgtactg
ggtgccaagtgatagaa...............aacaacatattaaaacgctcctgtggta
cttacctccgcgtgcgca
>M13733|CD79A*01|Mus musculus|F|EX3|
atccagtccctaggcccttcctggacatgggggaaggtaccaagaaccgcatcatcacag
cagaagggatcatcttgctgttctgtgcagtggtgccagggacgctgctgctattcagg
>M13733|CD79A*01|Mus musculus|F|EX4|
aaacggtggcaaaatgagaagtttggggtggacatgccagatgactatgaagatgaaaat
ctctatgag
>M13733|CD79A*01|Mus musculus|F|EX5|
ggcctgaaccttgatgactgttctatgtatgaggacatctccaggggactccagggcacc
taccaggatgtgggcaacctccacattggagatgcccagctggaaaagcca