'Food of the gods' genome sequence could make finest chocolate better

Dec 26, 2010
These are cacao flowers on a tree. Credit: Mark Guiltinan, Penn State

The production of high quality chocolate, and the farmers who grow it, will benefit from the recent sequencing and assembly of the chocolate tree genome, according to an international team led by Claire Lanaud of CIRAD, France, with Mark Guiltinan of Penn State, and including scientists from 18 other institutions.

The team sequenced the DNA of a variety of Theobroma cacao, considered to produce the world's finest chocolate. The Maya domesticated this variety of Theobroma cacao, Criollo, about 3,000 years ago in Central America, and it is one of the oldest domesticated tree crops. Today, many growers prefer to grow hybrid cacao trees that produce chocolate of lower quality but are more resistant to disease.

"Fine cocoa production is estimated to be less than 5 percent of the world cocoa production because of low productivity and disease susceptibility," said Guiltinan, professor of plant molecular biology.

The researchers report in the current issue of "consumers have shown an increased interest for high-quality chocolate made with cocoa of good quality and for , containing a higher percentage of cocoa, while also taking into account environmental and ethical criteria for cocoa production."

Currently, most cacao farmers earn about $2 per day, but producers of fine cacao earn more. Increasing the productivity and ease of growing cacao can help to develop a sustainable cacao economy. The trees are now also seen as an environmentally beneficial crop because they grow best under forest shade, allowing for land rehabilitation and enriched biodiversity.

The team's work identified a variety of gene families that may have future impact on improving cacao trees and fruit either by enhancing their attributes or providing protection from and insects that effect cacao trees.

This is a filled chocolate candy on a fork. Credit: Heather Annette Miller, Penn State

"Our analysis of the Criollo genome has uncovered the genetic basis of pathways leading to the most important quality traits of chocolate -- oil, flavonoid and terpene biosynthesis," said Siela Maximova, associate professor of horticulture, Penn State, and a member of the research team. "It has also led to the discovery of hundreds of genes potentially involved in pathogen resistance, all of which can be used to accelerate the development of elite varieties of cacao in the future."

Because the Criollo trees are self-pollinating, they are generally highly homozygous, possessing two identical forms of each gene, making this particular variety a good choice for accurate genome assembly.

The researchers assembled 84 percent of the genome identifying 28,798 genes that code for proteins. They assigned 88 percent or 23,529 of these protein-coding genes to one of the 10 chromosomes in the Criollo cacao tree. They also looked at microRNAs, short noncoding RNAs that regulate genes, and found that microRNAs in Criollo are probably major regulators of gene expression.

"Interestingly, only 20 percent of the genome was made up of transposable elements, one of the natural pathways through which genetic sequences change," said Guiltinan "They do this by moving around the chromosomes, changing the order of the genetic material. Smaller amounts of transposons than found in other plant species could lead to slower evolution of the chocolate plant, which was shown to have a relatively simple evolutionary history in terms of genome structure."

These are immature cacao pods on a cacao tree. Credit: Heather Annette Miller, Penn State

Guiltinan and his colleagues are interested in specific gene families that could link to specific cocoa qualities or disease resistance. They hope that mapping these gene families will lead to a source of genes directly involved in variations in the plant that are useful for acceleration of plant breeding programs.

The researchers identified two types of disease resistance genes in the Criollo genome. They compared these to previously identified regions on the chromosomes that correlate with disease resistance -- QTLs -- and found that there was a correlation between many the resistance genes' QTL locations. The team suggests that a functional genomics approach, one that looks at what the genes do, is needed to confirm potential disease resistant genes in the Criollo genome.

Hidden in the genome the researchers also found genes that code for the production of cocoa butter, a substance highly prized in chocolate making, confectionary, pharmaceuticals and cosmetics. Most cocoa beans are already about 50 percent fat, but these 84 genes control not only the amounts but quality of the cocoa butter.

Other genes were found that influence the production of flavonoids, natural antioxidants and terpenoids, hormones, pigments and aromas. Altering the for these chemicals might produce chocolate with better flavors, aromas and even healthier .

Explore further: Scientists tap trees' evolutionary databanks to discover environment adaptation strategies

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Quantum_Conundrum
1 / 5 (3) Dec 26, 2010
Sequencing 80% of the genes of one individual plant isn't really relavant. They need to do baseline sequencing across multiple variety of plants from multiple regions and nations to cross reference them and obtain all genes.

As our biologists and botanists continue to play god with GM technologies just remember this: Genetics is ultimately chemistry. When you change one gene that you hope gives you a good result, you probably are tinkering with other biochemical processes you don't even know about. This can give rise to contaminated food supplies, or make your entire crop vulnerable to some previously unknown virus, bacteria, or prion, or the crop itself could facilitate such a thing.

These companies should proceed with the utmost caution before actually implementing these technologies in food supplies.

This stuff could hold great promise, but blindly screwing around with things like a bunch of numbskulls could prove disasterous.
DamienS
3 / 5 (2) Dec 27, 2010
Sequencing 80% of the genes of one individual plant isn't really relavant.

It is if you're only interested in that particular variety of plant over all others.
They need to do baseline sequencing across multiple variety of plants from multiple regions and nations to cross reference them and obtain all genes

Why? Perhaps you should send them an email to put them on the right track.
As our biologists and botanists continue to play god with GM tech just remember this: Genetics is ultimately chemistry

You really don't understand genetics or chemistry, do you?
DamienS
5 / 5 (2) Dec 27, 2010
When you change one gene that you hope gives you a good result, you probably are tinkering with other biochemical processes you don't even know about. This can give rise to contaminated food supplies
...
These companies should proceed with the utmost caution before actually implementing these technologies in food supplies.

Which is probably a good thing that this type of research is done in the lab and/or under controlled conditions. But thanks for the tip.
blindly screwing around with things like a bunch of numbskulls could prove disasterous

Fortunately, numbskulls tend not to be employed in advanced research. There are no such restrictions for bloggers however.
Husky
not rated yet Dec 27, 2010
ah yes, cant wait before the engineers alter the sequence so that belgium chocolate with filling grows readymade on the trees, i loooooove chocolate.

Btw, in holland we nearly allmost speak of cacao while in the english also cocoa is used, what is the reason behind that?
Djincs
1 / 5 (1) Dec 27, 2010
@Quantum_Conundrum
Like it or not this is only the beginning of the gm tehnology being applied more and more, the cry of the people knowing shits of biology but shure that logical altering of the genome is bad(no evidence for that) and will doom us all wont be regarded, sooner the better!Still i hope that there will be more people that will by this product , which will be more fine , healty and environmental friendly(natural resistance= no chemicals). Good luck science, but I am shure it is a matter of time, it will be done!
And for the name of cocoa, it is really interesting , the latin is teobroma(the food of the gods) cacao, in my country we say cacao,and in brasil it is still cacao, i read somewhere the row material is cacao, and the cooked one is cocoa......
epsi00
not rated yet Dec 27, 2010
Quantum_Conundrum is the expert on this site and his knowledge extends from astrophysics to plants biology and genetics and maybe UFO's. So don't argue with him, he knows it all.
Djincs
1 / 5 (1) Dec 27, 2010
And something more, why people dont test and fear this "natural" mutants-all the new strains of plants we eat, despite the fact many of them are obtained by emmiting radiation or artificially some mutagenic chemicals used, but when scientist try to put some thought in the proces-it is totaly wrong!!!! So funny and stupid, and if the new gene that is put is so wrong why then there are many hybrids that combine many new traits in one organism......INSANITY, leave the scientist alone they know what they are doing!The product will be tested if it is not ok then it wont hit the market!
Djincs
1 / 5 (1) Dec 27, 2010
I dont defend all gmo, but when you work with non harful dna(dna that is not coding anithing poisonous), the chance of the genome to start to produse something harmfull is the same as with all natural mutation and all radiation and mutagenic substances used in agriculture which is produsing lots of new stuf constantly!
Djincs
not rated yet Dec 27, 2010
It is really easy just to rate 1, you have posted here, defend your position and point out where I am wrong, or you are like the people knowing gm is really bad but you actually dont know what is so wrong with it....
Quantum_Conundrum
1 / 5 (2) Dec 27, 2010

It is if you're only interested in that particular variety of plant over all others.
Why? Perhaps you should send them an email to put them on the right track.


Because one individual isn't representative of an entire species gene pool, you moron. If it was, every human would have down syndrome, hemaphylia, ALD, and every other disorder all at the same time.

You really don't understand genetics or chemistry, do you?


Does acing chemistry and pathophysiology make you look like a dumb shit?

You should know that the psuedo-science of "junk dna" was recently admitted to be false by the mainstream as well, just as I have been saying for like, well, forever.
Quantum_Conundrum
1 / 5 (2) Dec 27, 2010
Djincs:

Almost everyone on this site is an extreme, radical progressive. They promote world population decrease t oabout a billion, and they pretty much value any technological advancement as greater than human life, evidenced by the fact that they promote the wholesale slaughter of human embryos and fetus through stem cell research and abortion.

You'll find it difficult, if not impossible, to reason with any of them.

You'll also find most of them lack critical thinking skills, and are only capable of parroting the mainstream theory, and insulting anyone who objects.

Of course, if you don't agree with the mainstream practice or theory, you must be "uneducated" or "stupid," etc.
Djincs
not rated yet Dec 27, 2010
First i dont think to be progresive is wrong it depend how radical it is. Second I am pretty shure more embryos are killed due to not wonted pregnancy, science cant compare with this proces even a bit.
In the case i dont agree with the all anty gm propaganda at all-it is gm then ban it no questions(this lack any reasoning dont you think)!!!wtf! We live in a world where this has to be imposible and still it happens! Really disapointing for science, and all this shows the big ignorance which is everywhere.
DamienS
not rated yet Dec 27, 2010
Because one individual isn't representative of an entire species gene pool, you moron.

Straw man argument. They're studying exactly what's of interest to them. How silly is it to presume you know better what they should be doing and which methodology they should be using?
If it was, every human would have down syndrome, hemaphylia, ALD, and every other disorder all at the same time.

Conclusions based on straw man arguments don't strengthen your case. You should quit while you're behind.
Does acing chemistry and pathophysiology make you look like a dumb shit?

I dunno, I never professed to be an ace.
You should know that the psuedo-science of "junk dna" was recently admitted to be false by the mainstream as well, just as I have been saying for like, well, forever.

A non sequitur, but okay, super.
VOR
5 / 5 (2) Dec 28, 2010
re Quantum/ his ilk: an irony of our culture is that 'progressive' for the most part, means literally that. Women's rights, black rights, gay rights, evolution over creation, labor rights, healthcare,...these were/are progress. Those other- minded are literally regressive. Yet we continue to give credence to regression because its what a significant part of us 'think they want'. I think part of the reason for this is that our leanings are somewhat innate. For example its a documented fact that conservatives are more paranoid and less empathic than liberals. Conservative/regressive thinking/leadership should be relagated to its suited roles (like military/police, etc). Leave the decisions for what is best for the bulk of the country to those that care about people from different races/religions/sexual orientation/and wealth classes than thier own.
CarolinaScotsman
not rated yet Dec 31, 2010
I remember chocolate. It's that stuff my wife consumes all of before I know it's in the house.
ekim
not rated yet Jan 01, 2011
When scientists create a hybrid of a pea and nut, that can be turned into butter and is lethal to a small portion of the population, I will then say they are playing God.

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