University of Southern California, Los Angeles, CA, USA.
Am J Med Genet A. 2013 Jul;161A(7):1817-24. doi: 10.1002/ajmg.a.35957. Epub 2013 May 22.
Chimerism occurs when an organism contains cells derived from more than one distinct zygote. We focus on monochorionic dizygotic twin blood chimerism, and particularly twin-twin transfusion syndrome in such pregnancies. For years, researchers have understood chimerism to be a common phenomenon in cattle. Although, this review will not delve deeply into animal chimerism, an understanding of chimerism in the animal world can provide clues regarding health implications for human chimeras. This report serves two purposes: an update and assessment of the twins we reported previously in 2010 [Assaf et al., 2010] and a review on dizygotic monochorionic chimeric twins. First, our updated assessment of the twins shows no identifiable regression of Müllerian sex derivatives in the female, and normal neurodevelopment was documented in both. Our research has suggested several key points; one that blood chimerism persists from fetal life to at least age two years. Second, chimerism in humans is not as rare as previously thought, although it has been studied only recently. Third, assisted reproductive technologies appear to increase the risk of monochorionic dizygotic twin pregnancies.
嵌合体是指一个生物体含有来自不止一个明显受精卵的细胞。我们专注于单绒毛膜双羊膜囊双胎的血液嵌合体，特别是这种妊娠中的双胎输血综合征。多年来，研究人员已经了解到嵌合体在牛群中是一种常见现象。尽管本综述不会深入探讨动物嵌合体，但了解动物世界中的嵌合体可以为人类嵌合体的健康影响提供线索。本报告有两个目的：更新和评估我们在 2010 年报告的双胞胎[Assaf 等人，2010]，以及对双绒毛膜单羊膜囊嵌合双胞胎的综述。首先，我们对双胞胎的最新评估显示，女性的 Müllerian 性衍生物没有可识别的退化，并且在两者中都记录了正常的神经发育。我们的研究提出了几个关键点；一个是血液嵌合体从胎儿期持续存在到至少两岁。其次，人类嵌合体并不像以前认为的那样罕见，尽管最近才对其进行了研究。第三，辅助生殖技术似乎增加了单绒毛膜双羊膜囊双胎妊娠的风险。
