passages.id: split_5_test_1315_passage
passages.type: progene_text
passages.text: In addition to this predominant ( 75 % ) form , 5 - 10 % of pituitary GH is present as a 20 kDa protein that has an amino acid ( aa ) sequence identical to the 22 kDa form except for a 15 aa internal deletion of residues 32-46 as a result of an alternative splicing event .