Gamma chains make up the fetal hemoglobin F, in combination with alpha chains. {ECO:0000269|PubMed:11514664, ECO:0000269|PubMed:22096240, ECO:0000269|PubMed:6198905}. This is the function of HBG1 (hemoglobin subunit gamma 1, ENSG00000213934).