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主题:【原创】吃饭问题主要归功于前30年 -- hwd99

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家园 为啥剧毒的东西就是有巨大的危害呢?

我不明白为啥您认为剧毒的东西就有巨大的危害呢?我没有任何一句话说过转基因的食物有危害是因为剧毒吧?

相反,我认为毒蜘蛛,毒蛇,毒蘑菇存在的很合理。

至于转基因的知识,我去年下半年才拿过一个法国转基因工程某领头人的课。虽然法国人在转基因研究上并不是最先进,但是她老人家的介绍比你说的科普还是靠谱的多吧?(她的课没有评论,是对基因工程的介绍)

我的观点是基因工程导致物种变异速度过快,生态系统可能不能承受。而生态系统自身的对应发展,也可能是转基因食物丧失其所谓杀虫除草等功效。对未知基因段的不理解,有可能造成将来的灾难。当然还有特定基因逃逸等等问题。在这些问题得不到解答的情况下,大肆推广转基因食物无疑是短视的。这和剧毒的东西有一毛钱关系?

别东拉西扯什么螃蟹之类的事情,那是一回事吗?他们是存在且适应生态系统,而且生态系统适应之的。不就事论事,举这样的例子跟转基因一点关系都没有。比如,有人长期缺碘,导致大脖子病(一开始的缺碘是没有什么明显的反应的),而反对转基因,你觉得有意义吗?

抗生素咋不提了?

至于转基因的危害,超级杂草你听过吧?超级害虫在转基因大规模推广的湖北也已经出现,这是啥?转基因的好处?下面是wiki的介绍,有空好好看一下。至于“说句诛心的话,除了一知半解和用心不良以及受人蛊惑的人以外,都是支持转基因食品的大规模应用的。 ”,原来欧洲人都是“一知半解和用心不良以及受人蛊惑的人”。

学别人说话,一点创意都没有。

Genetically modified plants can spread the trans gene to other plants or – theoretically – even to bacteria. Depending on the transgene, this may pose a threat to the environment by changing the composition of the local ecosystem. Therefore, in most countries environmental studies are required prior to the approval of a GM plants for commercial purposes, and a monitoring plan must be presented to identify potential effects which have not been anticipated prior to the approval.

Little research has been conducted on human and animal health. However, in most countries every GM plant is tested in feeding trials to prove its safety, before it is approved for use and marketing. The project GMO-Safety collects and presents biosafety research on GMOs with more in-depth information on this topic.[1]

The potential impact on nearby ecosystems is one of the greatest concerns associated with transgenic plants.

Transgenes have the potential for significant ecological impact if the plants can increase in frequency and persist in natural populations. These concerns are similar to those surrounding conventionally bred plant breeds. Several risk factors should be considered:

Is the transgenic plant capable of growing outside a cultivated area?

Can the transgenic plant pass its genes to a local wild species, and are the offspring also fertile?

Does the introduction of the transgene confer a selective advantage to the plant or to hybrids in the wild?

Many domesticated plants can mate and hybridise with wild relatives when they are grown in proximity, and whatever genes the cultivated plant had can then be passed to the hybrid. This applies equally to transgenic plants and conventionally bred plants, as in either case there are advantageous genes that may have negative consequences to an ecosystem upon release. This is normally not a significant concern, despite fears over 'mutant superweeds' overgrowing local wildlife: although hybrid plants are far from uncommon, in most cases these hybrids are not fertile due to polyploidy, and will not multiply or persist long after the original domestic plant is removed from the environment. However, this does not negate the possibility of a negative impact.

In some cases, the pollen from a domestic plant may travel many miles on the wind before fertilising another plant. This can make it difficult to assess the potential harm of crossbreeding; many of the relevant hybrids are far away from the test site. Among the solutions under study for this concern are systems designed to prevent transfer of transgenes, such as Terminator Technology, and the genetic transformation of the chloroplast only, so that only the seed of the transgenic plant would bear the transgene. With regard to the former, there is some controversy that the technologies may be inequitable and might force dependence upon producers for valid seed in the case of poor farmers, whereas the latter has no such concern but has technical constraints that still need to be overcome. Solutions are being developed by EU funded research programmes such as Co-Extra and Transcontainer.

There are at least three possible avenues of hybridization leading to escape of a transgene:

Hybridization with non-transgenic crop plants of the same species and variety.

Hybridization with wild plants of the same species.

Hybridization with wild plants of closely related species, usually of the same genus.

However, there are a number of factors which must be present for hybrids to be created.

The transgenic plants must be close enough to the wild species for the pollen to reach the wild plants.

The wild and transgenic plants must flower at the same time.

The wild and transgenic plants must be genetically compatible.

In order to persist, these hybrid offspring:

Must be viable, and fertile.

Must carry the transgene.

Studies suggest that a possible escape route for transgenic plants will be through hybridization with wild plants of related species.

It is known that some crop plants have been found to hybridize with wild counterparts.

It is understood, as a basic part of population genetics, that the spread of a transgene in a wild population will be directly related to the fitness effects of the gene in addition to the rate of influx of the gene to the population. Advantageous genes will spread rapidly, neutral genes will spread with genetic drift, and disadvantageous genes will only spread if there is a constant influx.

The ecological effects of transgenes are not known, but it is generally accepted that only genes which improve fitness in relation to abiotic factors would give hybrid plants sufficient advantages to become weedy or invasive. Abiotic factors are parts of the ecosystem which are not alive, such as climate, salt and mineral content, and temperature. Genes improving fitness in relation to biotic factors could disturb the (sometimes fragile) balance of an ecosystem. For instance, a wild plant receiving a pest resistance gene from a transgenic plant might become resistant to one of its natural pests, say, a beetle. This could allow the plant to increase in frequency, while at the same time animals higher up in the food chain, which are at least partly dependent on that beetle as food source, might decrease in abundance. However, the exact consequences of a transgene with a selective advantage in the natural environment are almost impossible to predict reliably.

It is also important to refer to the demanding actions that government of developing countries had been building up among the last decades.

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