Subject: Onions without tears

From: [email-masked] (Joshua Senders)
Date: 1 May 1995 15:34:20 GMT

I am currently doing a genetic engineering project and need some information 
on the possibility of creating onions that do not make people tear.  Please 
let me know the part of the onion that makes you tear and if it is possible to 
remove this through genetic engineering.  If this is the wrong newsgroup,I'm 
sorry and please forward me to the correct one.  

Please e-mail your answer to [email-masked]

Thank you in advance.

Kim

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From: [email-masked] (Ray Dobert)
Date: 3 May 1995 14:30:00 -0700

Kim and/or Joshua,

>From  what I can determine the compound that makes you cry (or to be more
specific the lachrymatory factor -from the latin 'lacrimatio' to weep) is
thiopropanal S-oxide.  I'm not sure how much biochemisty and enzymology is
known about the synthesis of this compound.  

In terms of your question, I would imagine that you could, given enough
time and money, track down an enzyme essential for thiopropanal S-oxide
production and use genetic engineering to reduce or eliminate its
expression, resulting in a cryless onion.  Classical breeding and
selection may have already been used to acheive the same result.  

I'll send you a short list of references on the topic in a separate post.

Ray Dobert
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From: Gary Poyssick <[email-masked]>
Date: 15 May 1995 20:36:48 GMT

Put the onion in the freezer for ten minutes before you dice, chop, or 
slice it and you can eliminate the need to modify their genetic 
structure. The same stuff makes you cry makes you want to eat them.