We already know that cannabis lowers sperm count, but new research suggests that the drug actually causes changes to the sperm itself – which might have implications for the health of a potential baby.我们都告诉大麻不会减少精子数量,但新的研究指出,大麻实质上或造成精子本身发生变化–有可能对将要出生于的宝宝的身体健康产生影响。For a study published today in the journal Epigenetics, scientists at Duke University compared the sperm of two groups of rats: those who had been given tetrahydrocannabinol (THC), the psychoactive ingredient in cannabis, and those who had not. Then they compared the sperm of 24 human men who smoked marijuana weekly versus a control group who used marijuana no more than 10 times in their life and not at all in the past half-year. In both cases – rats and humans – marijuana changed how genes work in sperm cells.《表观遗传学》期刊今日公开发表了一篇研究:杜克大学的科学家将两组大鼠的精子展开了对比:一组大鼠被静脉注射了四氢大麻醇(THC,大麻中的精神活性成分),另一组没。之后,他们核对了每周大麻大麻的24位男性的精子与一生中用于大麻不多达10次的男性对照组(过去半年未曾吸过)的精子。



在这两种情况下–大鼠和人类–大麻都转变了基因在精子细胞中的起到。Think of your DNA as a list of instructions for making proteins, and genes as small subsets of that list. Our body has little chemical tags (called methyl groups) that get added to the DNA at specific regions, explains Susan Kay Murphy, a professor of gynecology at Duke and co-author of the study. These chemicals dont mutate the genes themselves, but they do affect how theyre used, like deciding which instructions are followed and which arent.将DNA视作产生蛋白质的指令列表,并将基因看做列表中的子集。我们的身体完全没可以在特定区域加到到DNA中的化学标签(称作甲基),杜克大学的妇科学教授以及本研究的联合作者苏珊·凯·墨菲说明道。


这些化学物本身会转变基因,但它们不会影响基本的用于方式,例如:哪些指令该遵循,哪些不应遵循。In both rats and humans, the cannabis affected many different genes involved in two different pathways. (Think of pathways as another set of instructions, this time for regulating various bodily functions.) One is important for organs to reach full size, and one plays a role in cancer and suppressing tumors. That just blows my mind, says Murphy. How do you even reconcile that, biologically, an entire pathway is going to be affected by these changes?在大鼠和人类的实验中,大麻影响了牵涉到两种有所不同途径的许多有所不同基因。(将途径视为另一组指令,用作调节身体各种功能的指令。)一个对于器官超过原始尺寸十分最重要,另一个在癌症和诱导肿瘤中发挥作用。

这一找到令其我大吃一惊,墨菲说。从生物学角度来看,我们又该如何协商这一变化,整个途径将不会受到这些变化的影响吗?This doesnt mean that smoking cannabis will lead future children to be more vulnerable to cancer. Murphy is very clear that this is a pilot study originally intended to see if cannabis even has any effect of this kind on sperm. The sample size is small, and they didnt control for the concentration of THC the human recruits smoked. The scientists did, however, measure THC in the urine and noted that more THC in the urine correlated with more changes.这并不是说道,大麻大麻不会造成即将出生于的宝宝更加易患癌症。墨菲传达的十分确切:这是一项试点研究,目的研究大麻否不会对精子产生影响。