Lockwood D H, Coppenhaver D H, Ferrell R E, Daiger S P
Biochem Genet. 1984 Feb;22(1-2):81-8. doi: 10.1007/BF00499288.
X-linked polymorphic variation of thyroxin-binding globulin (TBG) is observed in several human groups. Isoelectric focusing of plasma samples labeled in vitro with [125I]thyroxin, followed by autoradiography, also reveals genetically determined polymorphic electrophoretic variation in baboon TBG. The protein detected by this method in baboon plasma is immunologically similar to human TBG and is distinct from the other thyroxin-binding proteins, albumin and prealbumin. The isoelectric patterns of human and baboon TBG are very similar and both have an isoelectric range of pH 4.1 to 4.5. The baboon TBG polymorphism is inherited in a two-allele X-linked fashion, with a frequency of 72% for the "common" allele and 28% for the "slow" allele. A survey of seven other primate species including African green monkey, bonnet macaque, chimpanzee, crab-eating macaque, gorilla, rhesus monkey, and spider monkey revealed no polymorphic variation in TBG, although isoelectric patterns were similar to the human and baboon patterns. In addition, samples from pregnant chimpanzees demonstrate a pronounced quantitative anodal shift in relative band densities, a shift also observed in pregnant humans. This shift was not observed in samples from pregnant baboons. TBG should prove to be a useful X-linked genetic marker in baboons and provides a model of serum protein changes in pregnancy, at least in humans and chimpanzees.
在多个人类群体中观察到甲状腺素结合球蛋白（TBG）的X连锁多态性变异。用[125I]甲状腺素体外标记血浆样本，随后进行放射自显影，也揭示了狒狒TBG中由基因决定的多态性电泳变异。通过这种方法在狒狒血浆中检测到的蛋白质在免疫学上与人类TBG相似，并且与其他甲状腺素结合蛋白白蛋白和前白蛋白不同。人类和狒狒TBG的等电模式非常相似，两者的等电范围均为pH 4.1至4.5。狒狒TBG多态性以双等位基因X连锁方式遗传，“常见”等位基因的频率为72%，“慢”等位基因的频率为28%。对包括非洲绿猴、帽猴、黑猩猩、食蟹猕猴、大猩猩、恒河猴和蜘蛛猴在内的其他七种灵长类动物的调查显示，TBG没有多态性变异，尽管等电模式与人类和狒狒的模式相似。此外，怀孕黑猩猩的样本显示相对条带密度有明显的定量阳极移动，这种移动在怀孕人类中也观察到。在怀孕狒狒的样本中未观察到这种移动。TBG应该被证明是狒狒中一种有用的X连锁遗传标记，并为怀孕时血清蛋白变化提供了一个模型，至少在人类和黑猩猩中是这样。
