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(歡迎翻印、流通本文及網路連接；欲做其他用途，請先連絡作者易象乾博士。電郵地址：epstein@sfsu.edu)
為了生產不再倚賴石油為原料的塑膠，一些科學家通過基因工程，培育了在本身的莖部組織生產塑膠的植物。他們聲稱此種植物約在六個月內分解
。(詮35)如果這些基因經由與近親的相互授粉，或
其他方式流布到野外，那麼我們面對的前景是，天然的土地上散落著塑膠葉脈的腐敗葉子。且不論在美學角度看來多刺眼，更是因塑膠有其實質上的危險，它能擾亂整個食物鏈，無脊椎動物吃下後，本身又被其他動物吞食。以此類推，如果主要的食物本身是不可食的，或有毒的，那麼整個食物鏈可能相繼死亡。(註36
)
另一個「高明的主意」，是以基因工程培育具蠍子毒性的植物，昆蟲採食後就被殺死。縱然一位傑出的基因學家已經警告過，基因可能橫向轉移到昆蟲本身，或許經由牠們，將毒性注射到人體內，然而對這項「高明的主意」的研究與實地試驗，仍舊進行著。(註37)
動物
以基因工程培育新類型的蟲、魚、鳥獸，具有擾亂自然生態系統的潛能，通過牠們因基因改變而塑造的行為模式，能取代天然品種，擾亂其他品種的平衡。
動物的應用所牽涉的道德問題中，較為棘手的是前文所提到的「生命異種製版( xenographs )
」的創製，其中往往涉及到人類基因的植入。(見以下段落。)姑不論創製新動物時植入的基因是否為人類的基因，「異種製版」乃為供給人類使用而創造的，為企業的利益而取得專利，罔顧動物的痛苦、感覺與思想，或其天然的生活模式。
附註:
35. 「以轉移基因方式種植，能生化分解的塑 膠，又稱為polyhydroxyalkanotes或PHA's，第一批樣品已運往美國和歐洲的塑膠公司。麻薩諸塞州劍橋市的Metabolix公司，己經得到一項轉移基因科技的美國專利權，將基因植入高效率，使用轉移基因生物的發酵系統，以及實地農作物，以生產塑膠，在成本方面，最終將能與以石油提煉，用於包裝材料
、紙尿片、盛盒、瓶子、垃圾袋的塑膠競爭。美國與歐洲的數家公司和研究所，正在為生產塑膠的轉移基因植物申請專利......。英國瓦衛大學的科學家，在轉移基因植物的生產方面，已有突破性的進展。而加拿大的研究人員，也快能以類似的轉移基因植物，製造塑膠。」(一九九六年三月，第四冊、第三期《生物訊息：農業生物科技評論》。
36.分子生物學家約翰﹒費根博士警告說，這些塑膠中所用的新成份，是可能對動物與人類有害的毒性油脂。因此，當相互授粉的情形發生在野生的蕓薹植物上時，野生的植物產生對鹿、兔子，其他野生動物，以及人類有害的物質。(私人通訊)
37.基因學家約瑟夫﹒康明斯警告說：「這種令人質疑的試驗)將蠍子的毒素基因植入一個昆蟲的濾過性病原體中，然後將補補貼貼的濾過性病原體
，噴撒在田間農作物上。動過手腳的濾過性病原體，具強大的威力，能消滅昆蟲，包括害蟲、牠們的天敵，和傳播花粉的媒介者。蠍子的毒素被人吃下
後，可能並不造成威脅，但是對於切割的傷口和未愈合的潰爛傷口造成的後果，令人擔憂。這種毒素經常是過敏原，以及神經毒素。食物過敏引發的後果，包括偏頭痛乃至死亡。如果一個小型的實地試驗，沒有妥善的籌劃及控制，將帶來切身的危險。基因的重組，是此類試驗中的重要考量，蠍子的毒素基因可通過重組，而傳播到吸血或是吸花蜜的昆蟲。得到毒素基因的濾過性病原體，將建立新的生意優勢，形成可畏的寄生蟲。」(一九九六年八月
，第一冊《基因補貼的憂慮》第三頁。)
待續
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(permission is granted to reproduce this
article, to distribute it without charge, and to provide
links to it. Please contact the author at epstein@sfsu.ed
regarding other uses.)
So that we would not have to be dependent
on petroleum-based plastics, some scientists have
genetically engineered plants that produce plastic within
their stem structures. They claim that it biodegrades in
about six months.35 If the genes escape into the
wild, through cross-pollination with wild relatives or by
other means, then we face the prospect of natural areas
littered with the plastic spines of decayed leaves. However
aesthetically repugnant that may seem, the plastic also
poses a real danger. It has the potential for disrupting
entire food-chains. It can be eaten by invertebrates, which
are in turn eaten, and so forth. If primary foods are
inedible or poisonous, then whole food-chains can die off.36
Another bright idea was to genetically
engineer plants with scorpion toxin, so that insects feeding
on the plants would be killed. Even though a prominent
geneticist warned that the genes could be horizontally
transferred to the insects themselves, so that they might be
able to inject the toxin into humans, the research and field
testing is continuing.37
ANIMALS
The genetic engineering of new types of insects, fish, birds
and animals has the potential of upsetting natural
ecosystems. They can displace natural species and upset the
balance of other species through behavior patterns that are
a result of their genetic transformation.
One of the more problematic ethical uses
of animals is the creation of xenographs, already mentioned
above, which often involve the insertion of human genes.
(See the section immediately below.) Whether or not the
genes inserted to create new animals are human ones, the
xenographs are created for human use and patented for
corporate profit with little or no regard for the suffering
of the animals, their feelings and thoughts, or their
natural lifepatterns.
NOTES:
35. "The first samples of transgenically grown biodegradable
plastics, or polyhydroxyalkanoates (PHA's), have been
shipped to plastics companies in the United States and
Europe. Metabolix Inc., of Cambridge, MA, has patented
transgenic technology in the US. that inserts genes into
transgenic highly efficient fermentation systems and field
crops to produce plastics, which will eventually be cost
competitive with petroleum- based plastics used in
packaging, diapers, containers, bottles, and garbage bags. A
number of companies and research institutions in the US. and
Europe are working to patent transgenic plants for plastic
production .... University of Warwick scientists in England
have made breakthroughs in transgenic plastic production,
while researchers in Canada are close to making plastics
from similar transgenic plants." (BIOINPQ A nA griadtural
Biaechrx1agy M onuor, Vol IV, No.3, March, 1996)
36. Dr. John Fagan, a molecular
biologist, has warned that the new constituents that are
used in these plastics are oils that are probably toxic to
animals and humans. Thus when cross-pollination occurs with
wild brassica, the wild plants produce things that are toxic
to the deer, rabbits, and other wildlife, as well as humans.
(Personal communication)
37. Geneticist Joseph Cummins warned:
"The questionable experiment is to insert a gene for
scorpion toxin into an insect virus then to spray the
tinkered virus onto produce crops in the field. The tinkered
virus is now highly potent in destroying insects both pests
and their natural predators and the pollinators. The
scorpion toxin may not be threatening to humans as a toxin
when it is eaten but its impact on cuts and open sores is a
concern. Such toxins are frequently allergens as well as
nerve toxins. Food allergy causes effects ranging from
migraine headache to death. The danger from a small field
test is tangible provided the experiment is not well thought
out and controlled. Genetic recombination is a significant
concern in such experiments. The scorpion toxin gene can be
spread by recombination to insects that suck blood as well
as insects that suck plant juice. The virus that acquires a
toxin gene will achieve a new ecological niche and is likely
to be a formidable parasite." (Gene Tinkering Blues 1:3,
August 1996)
~ To be continued
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