Hemoglobin subunit gamma-2 is a protein that in humans is encoded by the HBG2gene.[1]
Function
The gamma globin genes (HBG1 and HBG2, this gene) are normally expressed in the fetal liver, spleen and bone marrow. Two gamma chains together with two alpha chains constitute fetal hemoglobin (HbF) which is normally replaced by adult hemoglobin (HbA) at birth. In some beta-thalassemias and related conditions, gamma chain production continues into adulthood. The two types of gamma chains differ at residue 136 where glycine is found in the G-gamma product (HBG2) and alanine is found in the A-gamma product (HBG1). The former is predominant at birth. The order of the genes in the beta-globin cluster is: 5' - epsilon – gamma-G – gamma-A – delta – beta - 3'.[2]
References
↑Higgs DR, Vickers MA, Wilkie AO, Pretorius IM, Jarman AP, Weatherall DJ (May 1989). "A review of the molecular genetics of the human alpha-globin gene cluster". Blood. 73 (5): 1081–104. PMID2649166.
Gelinas R, Yagi M, Endlich B, et al. (1985). "Sequences of G gamma, A gamma, and beta genes of the Greek (A gamma) HPFH mutant: evidence for a distal CCAAT box mutation in the A gamma gene". Prog. Clin. Biol. Res. 191: 125–39. PMID2413469.
Anderson NL, Anderson NG (2003). "The human plasma proteome: history, character, and diagnostic prospects". Mol. Cell. Proteomics. 1 (11): 845–67. doi:10.1074/mcp.R200007-MCP200. PMID12488461.