Connor Davidson

The Science of Seedless – How You Can Genetically Engineer Grapes and Bananas to not Produce Seeds


Posted: Wednesday, December 16, 2009

by Connor Davidson

Ask yourself when was the last time you took a bite of a fruit such as a grape or a banana and had to spit out the seeds? In fact when was the last time you ever bought seeded bananas or seeded grapes? I for one can't. And did you even know that bananas had seeds? Obviously the bananas and the grapes did not simply spontaneously decide that they best stop producing seeds because it is an inconvenience to those human folks. We engineered them to.

And here is how…

In a normal fruit we have one set of genetic information. When the cell goes to divide it replicates its genetic information to give it two sets. It then pairs up with its partner (known as a homologue) at the middle of the cell. These then split up and we end up with one set at each end of the cell. The cell finally splits in half and we end up with four cells with one set of genetic information. This gives normal seeds.

This means that the cell can reproduce and thus forms seeds. The important thing to note is that we have an even number of sets of genetic information.

If we don't have an even number of sets of this genetic information the cell can't reproduce. The reason for this is that the production of seeds is a very selective process. The pieces of genetic information must all line up correctly. If we have more than three they can't all pair up so the seeds never fully forms.

So, if you don't want seeds in your grapes give them three sets of genetic information and they won't produce seeds. Simple. As. That.

This can also be put to other uses. In fish farms the breeders don't want the fish to go out and disrupt the environment (or they say they don't at least) by mating with other fish so they ensure that they get three sets of genetic information and thus are made sterile.

Furthermore, the extra genetic information has to go somewhere so we end up with bigger cells. Multiply the increase in size and you find that they are much bigger than their normal counterparts. So, now when you go to the supermarket you can get bigger grapes without any seeds in them (P.S. no euphemism intended).

About this time I bet you are wondering if grapes and bananas etc don't have seeds how do they reproduce. Well, those ones don't. However, we could always keep a stock of the normal seeded ones so we have some to grow more.

This is a good idea. We should always have a supply of the original so we can put things right if we mess up – though this is unlikely.

What you can do is cheat and make these seeds reproduce asexually (only one parent). All of the green thumbed gardeners will have guessed what is coming: cuttings.

If you cut off one vine, plant it and look after it, it will grow into another plant. Since there is only one parent we end up with a clone which too, will have three sets of genetic information and subsequently will not produce seeds.

So, the next time you go to the supermarket make sure you pick up a set of triploid (three sets) grapes that have undergone a process of augmented meiosis (cell division). Or the ones that say seedless on the label. It's your choice.         

 

Connor Davidson is a UK based writer. He writes on wide variety of topics with his main interest being science, maths and engineering.

Feel free to reprint these articles on your website by using the reprint button. If you have any questions or comments please post them below - I read all comments.

You can keep up to date with his writings by following him on twitter or Google+

Connor Davidson Top 100 Author on WryteStuff!

Connor Davidson Featured Columnist at WryteStuff!
This Article has been viewed 725 times. (Not updated in real-time.)
More comments
» left by Mogama
2 years 163 days ago.
118 fans. Follow Mogama on twitter!
Thanks, Connor. I agree, this is scientific writing that a layperson can actually understand. Now I don't have to be suspicious of those seedless grapes that I enjoy so much. It's all safe, right? ~mogama~
» left by Connor Davidson 2 years 162 days ago.
95 fans. Follow Connor Davidson on twitter!
I'm pretty very confident in them being safe. If you really look in-depth into the genetics you find you've not changed all that much.
 
Thanks for the comment.
» left by erin from california 2 years 162 days ago.
Nice one...
» left by Connor Davidson 2 years 162 days ago.
95 fans. Follow Connor Davidson on twitter!
Thanks for the comment.
» left by Richard Vail
2 years 161 days ago.
60 fans.
Thanks for the info...the seedless eating public salutes you!
 
Rich
» left by Connor Davidson 2 years 161 days ago.
95 fans. Follow Connor Davidson on twitter!
Thanks for the comment.
» left by Connor Davidson 2 years 161 days ago.
95 fans. Follow Connor Davidson on twitter!
Thanks for the comment.
» left by Cecil Nye
2 years 160 days ago.
8 fans.
very nicely done. I enjoy reading articles like this. Thank you
» left by Connor Davidson 2 years 159 days ago.
95 fans. Follow Connor Davidson on twitter!
Thanks for the comment.
» left by Marijo Phelps
2 years 160 days ago.
143 fans.
Not too long ago I was chomping away on grapes that I thought were seedless - crunch - sort of ruined the grapes! Marijo
» left by Connor Davidson 2 years 159 days ago.
95 fans. Follow Connor Davidson on twitter!
Yeah it is a bit of a kerfuffle.
 
Thanks for the comment.
» left by Sara Patterson
2 years 159 days ago.
5 fans.
Well written with great information that was easy to understand. Thank you. ~s
» left by Connor Davidson 2 years 158 days ago.
95 fans. Follow Connor Davidson on twitter!
Thanks for the comment.
» left by Peter English
2 years 158 days ago.
7 fans.
Good article. The grapes and bananas sounded okay but the fish idea left me feeling a bit creeped out!
» left by Connor Davidson 2 years 157 days ago.
95 fans. Follow Connor Davidson on twitter!
Thanks for the comment.
» left by Lorrie Davids
2 years 158 days ago.
96 fans.
Pretty cool, Connor. Genetics and groceries!
» left by Connor Davidson 2 years 157 days ago.
95 fans. Follow Connor Davidson on twitter!
Thanks for the comment.
» left by Miyoshi Grant
2 years 157 days ago.
4 fans.
i appreciated the article, i can tell you know a lot about the topic - although i'm wondering if you used the best title. i got a little confused too. but it's easy to tell you know a lot about your subject matter. best of luck to you!!!
» left by Connor Davidson 2 years 156 days ago.
95 fans. Follow Connor Davidson on twitter!
What is confusing about the title?
 
Thanks for the comment.
» left by Linda DeWitt
2 years 153 days ago.
Very interesting article Connor.
» left by Connor Davidson 2 years 152 days ago.
95 fans. Follow Connor Davidson on twitter!
Thanks for the comment.

More comments
We want your comments! If you can read this, you don't have javascript enabled, so you can't use this comment system. Please enable javascript.