《那些古怪又讓人憂心的問題》第67期:自體繁殖(1)
SELF-FERTILIZATION
Q. I read about some researchers who were trying to produce sperm from bone marrow stem cells. If a woman were to have sperm cells made from her own stem cells and impregnate herself, what would be her relationship to her daughter?
Q．我看到一些研究說，他們正在嘗試用人體骨髓幹細胞來生產精子。如果一個女性用她自己的骨髓幹細胞造出了一個精細胞，並使自己受孕，那麼她和她的女兒會是什麼關係？-R Scott LaMorte
——R．斯科特•拉莫爾特
A. TO MAKE A HUMAN, you need to put together two sets of DNA.
A．要想造成一個人類，你需要把兩套DNA拼到一起。In humans, these two sets are held in a sperm cell and an egg cell, each of which holds a random sample of the parents' DNA. (More on how that randomization works in a moment.) In humans, these cells are from two different people. However, that doesn't necessarily have to be the case. Stem cells, which can form any type of tissue, could in principle be used to produce sperm (or eggs).
對於人類，這兩套DNA分別位於精細胞和卵細胞中，其中每一套都是從父母那裏隨機取出來的一部分DNA。（很快我們會具體講到這個隨機過程。）對於人類，精細胞和卵細胞分別來自兩個不同的人，但如果你有能夠分化成任何細胞的幹細胞的話，事情就不是這樣了，理論上來說，幹細胞也可以被用來生產精細胞或者卵細胞。So far, nobody has been able to produce complete sperm from stem cells. In 2007, a group of researchers succeeded in turning bone marrow stem cells into spermatogonial stem cells. These cells are the predecessors to sperm. The researchers couldn't get the cells to fully develop into sperm, but it was a step. In 2009, the same group published a paper that seemed to claim they'd made the final step and produced functioning sperm cells.
到目前爲止，還沒有人能夠利用幹細胞製造出完整的精細胞。2007年一組研究人員成功地將骨髓幹細胞轉化成了精原細胞，這些細胞是精子的前體。研究人員無法將這些細胞完全轉化成精細胞，但這至少是一個進步。2009年，這些研究人員發表了一篇論文，看上去宣稱他們已經實現了最後一步，製造出了完整的具有功能的精細胞。There were two problems.
但是這裏有兩個問題。First, they didn't actually say they had produced sperm cells. They said they produced sperm-like cells, but the media generally glossed over this. Second, the paper was retracted by the journal that published it. It turns out the authors had plagiarized two paragraphs of their article from another paper.
首先，他們並沒有說他們製造出了精細胞，而是說製造出了類精子細胞，但媒體在報道時通常都打馬虎眼沒提。其次，發表論文的期刊撤下了這篇論文，因爲其中的兩個段落抄襲自其他論文。Despite these problems, the fundamental idea here is not that far-fetched, and the answer to R. Scott's question turns out to be a little bit unsettling.
雖然有這樣那樣的問題，但這個設想本身並非是天方夜譚，斯科特的問題的答案甚至讓人有些小激動。
