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IMGT reference sequences in FASTA format:

Amino acid sequences without 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) 
>AK007741|CD48*01|Mus musculus|F|EX1|[D1]|V-LIKE|
MCFIKQGWCLVLELLLLPLGTGFQ
>AK007741|CD48*01|Mus musculus|F|EX2|[D1]|V-LIKE|
GHSIPDINATTGSNVTLKIHKDPLGPYKRITWLHTKNQKILEYNYNSTKTIFESEFKGRV
YLEENNGALHISNVRKEDKGTYYMRVLRETENELKITLEVF
>AK007741|CD48*01|Mus musculus|F|EX3|[D2]|C-LIKE|
DPVPKPSIEINKTEASTDSCHLRLSCEVKDQHVDYTWYESSGPFPKKSPGYVLDLIVTPQ
NKSTFYTCQVSNPVSSKNDTVYFTLPCDL
>AK007741|CD48*01|Mus musculus|F|EX4|
ARSSGVCWTATWLVVTTLIIHRILLT
>CD48*01|Mus musculus|F|EX1-4|
MCFIKQGWCLVLELLLLPLGTGFQGHSIPDINATTGSNVTLKIHKDPLGPYKRITWLHTK
NQKILEYNYNSTKTIFESEFKGRVYLEENNGALHISNVRKEDKGTYYMRVLRETENELKI
TLEVFDPVPKPSIEINKTEASTDSCHLRLSCEVKDQHVDYTWYESSGPFPKKSPGYVLDL
IVTPQNKSTFYTCQVSNPVSSKNDTVYFTLPCDLARSSGVCWTATWLVVTTLIIHRILLT