Come For the Beautiful "Glass Gem" Corn; Stay for a Dose of Genetics

By Sarah Zhang | May 15, 2012 1:57 pm

glass gem corn

No, this isn’t Photoshop or a gemstone-studded trinket—just an ear of corn. Seedsman Greg Schoen of the Seeds Trust got this “Glass Gems” corn from his “corn-teacher,” a part-Cherokee man in his 80s. He planted the seeds, had a gorgeous harvest last fall, and posted the posts on Seeds Trust’s Facebook page in October. Then last week, the photos of the gem-like corn got picked up on the internet and went viral. Good luck trying to get your hands on any seeds now…

But kernel color is a fascinating—dare we say, colorful—topic in the annals of genetics research. For one, why are there so many vibrant colors in a single ear of corn? You don’t usually see flowers of different colors on a single tree. Each kernel is actually a different corn plant (or the seed of one) with a unique mix of genes inherited from its parents. That’s why counting up kernels of different colors in the more familiar purple and yellow corn cobs is a common way of teaching how pigment genes are inherited in Mendelian genetics.

glass gem corn

Kernel color has also been used to unravel an odd phenomenon in non-Mendelian inheritance: transposons, or jumping genes. Some types of corn have kernels mottled or streaked with a second color, which means some of its cells are producing a particular pigment but others are not. Transposons are stretches of DNA that jump from place to place in the genome, and landing in the middle of a pigment gene would alter the color of that cell. Barbara McClintock won a Nobel Prize for her discovery of transposons.

Even the relatively boring white or yellow corn you find in supermarkets has made big genetic leaps from grass to the ears of corn we eat today. These gem glass corn, however, might be too pretty to eat.

[via Agricultural Biodiversity]

Images via Seeds Trust

  • Rosie Redfield

    Can anyone point me to a more detailed discussion of the genetics of this particular corn strain? How many different mutant genes are involved, to generate all the different colours? And which alleles of which genes are they?

    And how is this corn propagated? If I plant a kernel from such an ear, and self-pollinate the resulting plant, would I get cobs with only one or two colours? What if I planted many kernels and let them cross pollinate?

  • Loonook

    Few questions:

    1.) What does it taste like?
    2.) Does it cross true or lose its awesome dynamic colors if not cultivated properly?
    3.) Where may I purchase this wonderful thing?



  • Corny

    These look gorgeous! I’ve tried planting corn kernels from indian corn cobs (available usually during Halloween in supermarts). They do germinate but never grow much before withering. Is there a secret to growing them?

  • Sarah Zhang

    I think we’re all curious about how it tastes and how to grow them! Seeds Trusts sells the glass gem corn, but it’s been so popular that they’ve sold out and their website is intermittently down. You can try it:

  • Social

    “Too pretty to eat” – my thoughts exactly

  • Sophie

    WOW! These are beautiful!

    Are these strains specifically colored to be like this or was this a side effect of another goal? Does the color/pigmentation change the nutritional value?

    I heard yellow pigmented foods (corn, bananas) have high concentrations of vitamin B. Does this change for the gem corn?


  • Brian

    It is not sweet corn. It is a flint type, but a great mix of colors. There is a helpful table in Mutants of Maize by Nueffer, Cole, and Wessler that describes the main genes that affect kernel color – aleurone and pericarp and the main interactions. Information is also available from MaizeGDB on each of the mutants: Aleurone ( ) Pericarp (

    To maintain the mix, these are probably sib mated and selected each generation for the range of colors. Obviously the colors are segregating and so you would have to make sure to maintain as many segregating as possible and not fix any of the alleles. If you wanted you could self out each color and make them homozygous and maintain the population as a synthetic. That way it could be recreated and increased in large quantities with predictable ratio of colors. But sib mating is a lot easier.

  • Rosie Redfield


    Yes, there could be four genes, each responsible for the production of a different pigment, and each with a + and a – allele (green+/-, yellow+/-. blue+/-, red+/-).

    But with crossing over and random assortment of genes into gametes and gametes into diploid kernels, that should give a lot of combinations but not very many nice-looking ones. If the + alleles are fully dominant to the – alleles, we’d get 32 combinations, most of which would be muddy-looking mixture colours (e.g. green+ yellow- red+ blue-), not lovely jewel tones. And if a +/- combination of alleles gave only half as much pigment as a +/+ combination, we’d have 81 combinations, again mostly muddy.

  • Stephen Thoams

    Thanks so much for this informative and thoughtful post. Just wanted to let you and your readers know that Native Seeds/SEARCH, one of the stewards of Glass Gem along with Seeds Trust, has added a blog with more on the story of this remarkable corn.

    Read about it here:

    Also, we have a waiting list on our site for those that wish to buy seed, available in Oct 2012. Thanks for spreading the word, and sharing the knowledge!


  • James Naranjo

    Too pretty to eat? Sorry, I’m with Loonook on this one. I’ll take one ear boiled and one wrapped in tin foil for the barbecue.

    “Tin foil”. Anyone want to guess my age?

  • Janet Davis

    Am I the only one who’s a little skeptical of these two shots? As a freelance writer/photographer, I have been following the Glass Gems seeds story this week and there is no digging beyond the breathtaking images and sentences-long “story”. The photo of the actual ears in their husks shows them to be indeed colourful, but not like these close-ups. Typical Indian corn simply doesn’t look these perfect kernels, with colour so well distributed. Yet no one has taken the initiative to do an interview, or ask how Greg Schoen got the seed. Carl Barnes was indeed a Cherokee heritage corn seed-saver, who apparently died at the age of 83 in Turpin OK. Who is Greg Schoen? I just think something this incredible-looking should be confirmed through normal journalistic practices.

  • Iain

    I hazard to guess that post digestion it is all brown.

  • Dave Christensen


    I am a lifetime breeder of Indian corn. I have not seen this corn, but I will express my opinion. YES it is real, and is not a photo touch-up. However you should know three things.
    1) There was tremendous lighting and photography. It may not look so gem-like in an ordinary setting.
    2) I am willing to bet that the corn photographed was recently picked and had over 15% moisture content, which makes it glow. In a month when it dries completely it will be somewhat less transparent.
    3) This particular ear with all the colors is hard to achieve. I wish I could breed them all like this, but ears like this are rare. To reproduce another ear like this one the right color of kernel on this ear must be planted, and I don’t know which color that is. If someone knows, please tell us. Also it must receive a good variety of colors carried through the pollen.

    I knew Carl Barnes and he had a beautiful Native spirituality. I wish he had lived to see this on the web.

    The Painted Mountain Corn that I grow has a soft flour starch for easy grinding and has high nutrition for human food. It also has vivid and amazing colors too. But it’s starch is opaque so does not have this hard glassy starch. You can see photos on my web site. Painted Mtn. is a stress hardy survival corn developed in Montana, and is saving lives around the world. It can be purchased from several companies.

  • Jam scorn

    where could I got it?

  • qfarms

    It was my blog that gone viral abt these gems corn

  • Jim

    Will it make good popcorn?


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