Spicy New Hybrids

    One of the most popular spices known to man is the chili pepper. It is used as a spice to add heat and flavor to many culinary dishes, and comes from the fruit of plants from the genus Capsicum, members of the nightshade family-- Solanaceae. There are currently 35 different species of peppers in the Capsicum family, which leads to constant changes in their genetic relatedness; and scientists recently discovered an entirely new host of chili hybrids that, "could be grown by crossing domesticated peppers with their wild cousins."

As scientists continued to improve their understanding of the relationship between Capsicum species and hybrids, they also stumbled upon a misidentification of several species that were wrongly characterized. The study published in the journal, PLOS ONE, explains, "Based on a phylogeny constructed by genotyping using single sequence repeat (SSR) markers and with a portion of the waxy locus, and through principal component analysis (PCA) of phenotypic data, we clarify the relationships among wild and domesticated Capsicum species." Yet, even then, the full phylogeny of Capsicum is still unresolved.

An upside to these newfound hybrids is that chilies tend to be rather difficult to cultivate and maintain. These hybrids will allow breeders to create chilies that are both, disease resistant and increase productivity. "Many of the many wild species have better disease resistance and so our findings could be valuable for identifying candidates for future breeding programs, potentially increasing productivity for food producers, and maybe even creating some new flavors to explore too!" lead author of the study, Catherine Parry explains. 

Finding new species and hybrids of food and spices can lead to great improvements and advances in both the world and our diets. I think it's great that we are constantly learning and adapting to these newfound scientific discoveries. Plus, who doesn't like a little "kick" in their food!

Links:

https://phys.org/news/2021-03-chilli-genetics-greater-variety-plates.html

https://www.biorxiv.org/content/10.1101/2020.11.30.403691v1

Bear Breeds and Evolution

     Is it possible to analyze the evolutionary history of all bears at the genome level? Now it is! Scientists have sequenced the entire genomes of four bear species. It shows that gene exchange between species occurs through extensive hybridization. DNA samples of different species were taken from European zoos that are important for both conservation and research. Through these studies, it discounts previous assumptions of hybrid bears occurring due to climate change.

     I too was under the impression that climate change played a huge role in different hybrids of bear species. According to the article, brown bears invade northern regions and polar bears move onto the sea ice later than usual due to changes in climate. This new genomic data showed there must have been gene flow between the polar and sun bears, however the two live in completely different geographic areas and thus have never met. The researchers explanation of this suggested an "intermediate host" has passed the genes on in various directions.




Bear Hybrids
Types of Bears

A Genetic Fix to Put the Taste Back in Tomatoes

Dr. Harry J. Klee and his colleagues from University of Florida, explain how the delicious taste of tomatoes has been drained over the decades. Your average tomatoes found at the supermarket contain a bland taste, sugar and chemicals. Over the course of years, they sequenced the full genome of 400 tomatoes heirloom, wild and modern. After analyzing they were able to identify 26 genes providing flavorful volatiles. Dr. Klee produced these tomatoes and held a taste panel of different groups. Between men and women, between young and old, between foodies and nonfoodies.  From the results he walked alway bothered, we have trained the young generations to pick the supermarket tomatoes than a good old flavorful tomato. For those who did enjoyed the tasty tomatoes or who is interested may for a small donation of $10 receive a packet of seeds of this new best-tasting heirloom and modern variety.

Why Don't Humans Have Much Neanderthal DNA in Them?

A long time ago, Neanderthal's and modern day humans diverged from a common ancestor, but only 1 of the 2 species did well.  The neanderthals did not just get wiped off the earth, since about 50,000 years ago, they interbred with modern humans as they were leaving Africa, leaving a small amount of their DNA behind.  And by small, I mean very small.  The question is, why is there such a small amount of DNA left over by the neanderthals, and why did the neanderthal human hybrids not survive well?  One answer is as simple as population size.  In smaller populations, natural selection is not as strong of a factor in the population, and so the neanderthals were subject to a lot of inbreeding, and overall the entire population developed and spread more and more mutations around within themselves.  Since these mutations did not stop them from breeding with each other, it can be assumed that all of these mutations built up, and eventually became a very large problem for  neanderthals.

This information also shows why not much neanderthal DNA remains in modern day humans.  Since the neanderthals already were so heavily mutated, when they bred with humans, they passed along their mutations to the hybrid offspring, who then either would have died from the mutations, or would have then passed them down again to their offspring, and so on.  Overtime this process makes it so that the small amount of DNA that was transferred from neanderthal to human was slowly lost, but not completely, resulting in a very small amount of their DNA found in modern humans.

I'm a little surprised that the answer to this problem is so simple.  All it really has to do with is population size, and I think that that is really interesting.  Granted the small population size does make a lot of sense, I didn't think to take into account that this means that there would be a lot of inbreeding occurring among the population, which also makes a lot of sense.  It is also pretty interesting that because of this initial inbreeding, that the major effects of it made the neanderthal human hybrids less likely to survive, and so the amount of neanderthal DNA in modern humans is so small.

http://www.nytimes.com/2016/11/09/science/neanderthal-dna-natural-selection.html?rref=collection%2Fsectioncollection%2Fscience&action=click&contentCollection=science&region=stream&module=stream_unit&version=latest&contentPlacement=58&pgtype=sectionfront 

http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1006340

Agronomist explores the genetics that allow hybrid plants to perform better than parents

       

    Jianming Yu of Iowa State University has helped recover the unknown mechanism behind heterosis. Which explains why some hybrids of sorghum plants out grow and out perform their parents.  For years agronomists and botanists were not sure why this occurred, the phenomenon was only partially understood.  The study focused on the link between a dominant allele of one gene with recessive allele of another.  Yu went out to answer the question:  "Where does that extra height come from if not from either parent?"
          Through research Yu explained that because most of sorghum plants are the offspring from a inbred fertilization that sometimes this causes genes to "cancel" each other out.  Yu also goes onto explain that multiple genes makeup up the height trait.   One could be responsible for base length, one responsible for stem length, therefore a different combinations from both parents could result in a taller plant.
          I feel like this article is one of more relevant articles to our class.  Specifically the first half of the semester where we studied more classical genetics.  I was impressed to fine that theories are still being put to use for further research purposes.

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Related Post

New Study Looks into Genetic Explanation for Heterosis in Corn

 



For over a hundred years, farmers used the concept of heterosis to increase crop yields. To take the most advantage of increased productivity, farmers cross two distinct lines of corn to produce a variety that performs much better than either of the two original strains. Much works has been done to study what lineages produce various types of corn, such as field corn and sweet corn. However, for all of the work that has done with corn hybrids, the genetic mechanism that makes this all possible remains a mystery – until now.

According to Science Daily, a research team comprised of individuals from the University of Bonn, Iowa State University, and the Max Plank Institute has proposed a genetic reason as to why heterosis works. Through state-of-the-art genetic sequencing technology, the researchers discovered genetic fingerprints suggesting that hybrid plants have more active genes than purelines. The increase in the amount of active genes allows hybrid plants to be more productive.

Perhaps the most exciting part of the article is its application to the real world. As food prices – especially corn prices – rise higher every day, there would be a great worldwide benefit if the researchers’ work could be used to produce corn crops with higher yields. Not only is corn used for human consumption, but it is also used for animal feed and biofuels as well. The researchers’ findings has the potential to have a major impact in the global economy.

Human Animal Hybrids Grown in Lab

For the past three years, British labs have secretly been creating up to 150 human animal hybrid embryos. Since the introduction of the 2008 Human Fertilization Embryology Act this british laboratory has upwards of 155 mixed embryos containing both animal and human genes and a variety of hybrids including animal eggs fertilized by human sperm; animal cells implanted with human nucleus "cybrids"; humans cells mixed with animal embryos also called "chimeras". The scientists are claiming that, by using these techniques, embryonic stem cells can be created and used to help cure many diseases. Although these hybrids sound promising in the possibilities in curing disease, ethically, many researchers are chastised for their work and many labs lost funding for this type of research. Many people do not believe in this type of research and are making is sound as though there will be a planet of the apes uprising but in fact, many lives can be saved using this research including the ability to use animals for human organ transplants. If we could use, for example pig organs for human transplants, the tens of thousands of people on the transplant list may not die waiting for help. Scientists are introducing humans genes into animals in hopes to lessen the number of transplants that are rejected in those who receive donor organs. Whatever your opinion is on the subject is your opinion but do the research before you begin to judge.