Baby boys are more sensitive to stress in the womb
子宫中的男婴对压力更敏感
May explain why maternal stress and disorders such as autism and schizophrenia are more common in boys
因受母体的压力和精神失常因素影响，所以，如自闭症和精神分裂症在男孩中较常见
A pregnant women can transmit the damaging effects of stress to her unborn child through the placenta, say researchers.
研究人员说，孕妇压力经胎盘对未出生婴儿有破坏性影响。
Scientists believe it could explain known links between maternal stress and disorders such as autism and schizophrenia, which are more common and serious in male offspring.
科学家认为因受母体的压力和精神失常这些因素影响，所以，如自闭症和精神分裂症在男孩中较常见较严重。
'Almost everything experienced by a woman during a pregnancy has to interact with the placenta in order to transmit to the foetus,' said lead researcher Dr Tracy Bale, from the University of Pennsylvania’s School of Veterinary Medicine in the U.S.
几乎女性怀孕期间所经历的一切都会经胎盘传递给婴儿，美国宾夕法尼亚大学兽医学学院负责此项研究的特雷西·贝尔说。
'Now we have a marker that appears to signal to the foetus that its mother has experienced stress.'
现在我们研究发现胎儿的表现信号与母亲所经历的压力因素有关。
The researchers studied female mice that were exposed to mild stresses such as the smell of foxes or unfamiliar noises during the first week of pregnancy. They identified an enzyme called OGT that was present at lower levels in the placentas of stressed mice than in unstressed mice.
经研究人员鉴定有压力的小白鼠比没有压力的小白鼠胎盘内的一种称为转移酶（OGT）的这种酶含量低。
Male offspring placentas also had lower natural levels of OGT than those attached to female offspring.
男性胎盘的转移酶也比女性胎盘的转移酶含量低。
Further research showed that cutting levels of OGT triggered changes in more than 370 genes in the brains of unborn mice.
进一步研究发现转移酶含量降低引起了未出生小白鼠大脑中370个基因发生变化。
Many of these genes play a role in functions critical to neurological development, such as energy use, protein regulation and creating nerve cell connections.
这些基因对神经发育功能起到关键作用，如精神状态、蛋白质调节、造神经细胞、连接神经细胞。
Analysis of human placentas discarded after the birth of male babies showed evidence of reduced OGT levels.
分析男婴出生后的胎盘，结果表明转移酶的含量降低了。
The results suggest that OGT may protect the brain during pregnancy. Males have less of the protein to begin with, placing them at greater risk if their mothers are stressed.
结果表明怀孕期间转移酶可保护大脑，最开始男性蛋白质较少，如果母亲有压力就会对男婴构成较大风险。
'We want to get to the point where we can predict the occurrence of neurodevelopmental disease,' said Dr Bale.
贝尔博士说，重点在于我们能预知神经发育疾病。
'If we have a marker for exposure, we can meld that with what we know about the genetic profiles that predispose individuals to these conditions and keep a close eye on children who have increased risks.'
如果我们发现这一迹象，再加上我们对基因结构的了解，预测个人对这些条件的了解并密切关注孩子们的风险增加情况。