DeSimone J, Schroeder W A, Shelton J B, Shelton J R, Espinueva Z, Huynh V, Hall L, Zwiers D
Blood. 1984 May;63(5):1088-95.
In the baboon (Papio species), the two nonallelic gamma-genes produce gamma-chains that differ at a minimum at residue 75, where isoleucine (I gamma-chain) or valine (V gamma) may be present. This situation obtains in baboons that are sometimes designated as Papio anubis, Papio hamadryas, and Papio papio. However, in Papio cynocephalus, although the I gamma-chains are identical with those in the above mentioned types, the V gamma-chains have the substitutions ala----gly at residue 9 and ala----val at residue 23. The V gamma-chains of P. cynocephalus are called V gamma C to distinguish them from the V gamma A-chains of P. anubis, etc. A single cynocephalus animal has been found to have only normal I gamma-chains and I gamma C-chains (that is, glycine in residue 9, valine in 23, and isoleucine in 75). When HbF is produced in response to stress with 5-azacytidine, P. anubis baboons respond with greater production than do P. cynocephalus, and hybrids fall between. Minimal data on P. hamadryas and P. papio suggest an even lower response than P. cynocephalus. As HbF increases under stress, the ratio of I gamma to V gamma-chains changes from the value in the adult or juvenile baboon toward the ratio in the newborn baboon. However, it does not attain the newborn value. The V gamma A and V gamma C-genes respond differently to stress. In hybrids, the production of V gamma A-chains exceeds that of V gamma C-chains. A controlling factor in cis apparently is present and may be responsible for the species-related extent of total HbF production. It may be concluded that the more primitive the cell in the erythroid maturation series that has been subjected to 5-azacytidine, the more active is the I gamma-gene.
在狒狒（狒属物种）中，两个非等位的γ基因产生的γ链至少在第75位氨基酸残基处存在差异，该位置可能存在异亮氨酸（Iγ链）或缬氨酸（Vγ链）。这种情况在有时被指定为东非狒狒、阿拉伯狒狒和豚尾狒狒的狒狒中存在。然而，在黄狒狒中，尽管Iγ链与上述类型的相同，但Vγ链在第9位氨基酸残基处有丙氨酸到甘氨酸的替换，在第23位氨基酸残基处有丙氨酸到缬氨酸的替换。黄狒狒的Vγ链被称为VγC，以区别于东非狒狒等的VγA链。已发现一只黄狒狒动物仅具有正常的Iγ链和IγC链（即第9位为甘氨酸，第23位为缬氨酸，第75位为异亮氨酸）。当用5-氮杂胞苷应激产生HbF时，东非狒狒的反应比黄狒狒更强烈，杂种则介于两者之间。关于阿拉伯狒狒和豚尾狒狒的最少数据表明其反应比黄狒狒更低。随着应激下HbF增加，Iγ链与Vγ链的比例从成年或幼年狒狒中的值向新生狒狒中的比例变化。然而，它并未达到新生狒狒的值。VγA和VγC基因对应激的反应不同。在杂种中，VγA链的产生超过VγC链。显然存在一个顺式控制因子，它可能是总HbF产生的物种相关程度的原因。可以得出结论，在红细胞成熟系列中接受5-氮杂胞苷处理的细胞越原始，Iγ基因就越活跃。
