[Polymorphism at codon 117 of the granulocyte-macrophage colony-stimulating factor (GM-CSF) gene]

A T-to-C substitution, replacing a hydrophobic isoleucine residue with a hydrophilic threonine residue in position 100 of a mature protein molecule, was found at codon 117 of the GM-CSF gene. The mutation frequencies were estimated in 51 DNA samples from healthy adult donors and also in 20 samples from patients with different neoplastic myeloid disorders. Almost equal substitution frequencies in patients and normal individuals were observed, suggesting that the defect was not associated with leukemia. Additionally the GM-CSF gene intron 1 sequence was refined.