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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) 
>AL391903|TREM1*01|Homo sapiens|F|EX1
MRKTRLWGLLWMLFVS
>AL391903|TREM1*01|Homo sapiens|F|EX2|[D]|V-LIKE
ELRAATKLTEEKYELKEGQTLDVKCDYTLEKFASSQ....KAWQIIRDGEMPKTLACTER
PS.....KNSHPVQVGRIILEDYHDHGLLRVRMVNLQVEDSGLYQCVIYQPP.KEPHMLF
DRIRLVVTK
>AL391903|TREM1*01|Homo sapiens|F|EX3
GFSGTPGSNENSTQNVYKIPPTTTKALCPLYTSPRTVTQAPPKSTADVSTPDSEINLTNV
TDII
>AL391903|TREM1*01|Homo sapiens|F|EX4
RVPVFNIVILLAGGFLSKSLVFSVLFAVTLRSFVP*
>BC017773|TREM1*01|Homo sapiens|F|EX1|splicing B
MRKTRLWGLLWMLFVS
>BC017773|TREM1*01|Homo sapiens|F|EX2|[D]|V-LIKE|splicing B
ELRAATKLTEEKYELKEGQTLDVKCDYTLEKFASSQ....KAWQIIRDGEMPKTLACTER
PS.....KNSHPVQVGRIILEDYHDHGLLRVRMVNLQVEDSGLYQCVIYQPPKEPHMLFD
RIRLVVTK
>BC017773|TREM1*01|Homo sapiens|F|EX3|splicing B
GFRCSTLSFSWLVDS*