PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

We each live in our own little world -- smellwise

2013-08-01
(Press-News.org) There are some smells we all find revolting. But toward a handful of odors, different people display different sensitivities—some can smell them, while some can't, or some find them appealing, while others don't. A pair of studies appearing online on August 1 in the journal Current Biology, a Cell Press publication, now identifies the genetic differences that underpin the differences in smell sensitivity and perception in different individuals. The researchers tested nearly 200 people for their sensitivity for ten different chemical compounds that are commonly found in foods. They then searched through the subjects' genomes for areas of the DNA that differed between people who could smell a given compound and those who could not. This approach—known as a genome-wide association study—is widely used to identify genetic differences.

The researchers, led by Sara Jaeger, Jeremy McRae, and Richard Newcomb of Plant and Food Research in New Zealand, found that for four of the ten odors tested, there was indeed a genetic association, suggesting that differences in the genetic make-up determine whether a person can or cannot smell these compounds. The smells of these four odorants are familiar, for those who can smell them (though their names may not be): malt (isobutyraldehyde), apple (β-damascenone), blue cheese (2-heptanone), and β-ionone, which smells floral to some people and is particularly abundant in violets.

"We were surprised how many odors had genes associated with them. If this extends to other odors, then we might expect everyone to have their own unique set of smells that they are sensitive to. These smells are found in foods and drinks that people encounter every day, such as tomatoes and apples. This might mean that when people sit down to eat a meal, they each experience it in their own personalized way," says Jeremy McRae.

When McRae and colleagues compared the differences in sensitivities between human populations in different parts of the world, they found no sign of regional differentiation. This means that, for instance, a person in Asia is just as likely to be able to smell one of these compounds as someone in Europe or Africa. What's more, the ability to smell one of the compounds doesn't predict the ability to smell the other. So, if you are good at smelling blue cheese, it doesn't mean you're necessarily good at smelling the apple next to it.

So, which are the genes that determine our ability to perceive certain odors? McRae and colleagues found that the genetic variants associated all lie in or near genes that encode so-called odorant or olfactory receptors. The odorant receptor molecules sit on the surface of sensory nerve cells in our nose. When they bind a chemical compound drifting through the air, the nerve cell sends an impulse to the brain, leading ultimately to the perception of a smell.

In the case of β-ionone, the smell associated with violets, McRae and colleagues managed to pinpoint the exact mutation (a change in the DNA sequence) in the odorant receptor gene OR5A1 that underlies the sensitivity to smell the compound and to perceive it as a floral note—people who are less good at smelling β-ionone also describe the smell differently, as sour or pungent, and are less likely to find it pleasant.

"Knowing the compounds that people can sense in foods, as well as other products, will have an influence on the development of future products. Companies may wish to design foods that better target people based on their sensitivity, essentially developing foods and other products personalized for their taste and smell," says Richard Newcomb.

So, next time you are buying violets for your sweetheart, you can see if he or she can smell them and perform your own ad hoc genetic test.

### Current Biology, Jaeger et al.: "A Mendelian trait for olfactory sensitivity affects odor experience and food selection."

Current Biology, McRae et al.: "Identification of regions associated with variation in sensitivity to food-related odors in the human genome."


ELSE PRESS RELEASES FROM THIS DATE:

Neuroscientists find protein linked to cognitive deficits in Angelman syndrome

2013-08-01
A team of neuroscientists has identified a protein in laboratory mice linked to impairments similar to those afflicted with Angelman syndrome (AS)—a condition associated with symptoms that include autism, intellectual disability, and motor abnormalities. The findings appear in the journal Cell Reports. "By isolating a protein that contributes to cognitive deficits in Angelman syndrome, these findings mark a step forward in not only addressing AS, but perhaps other developmental disorders as well," said Eric Klann, a professor in New York University's Center for Neural ...

Boning up: McMaster researchers find home of best stem cells for bone marrow transplants

2013-08-01
Hamilton, ON (August 1, 2013) –McMaster University researchers have revealed the location of human blood stem cells that may improve bone marrow transplants. The best stem cells are at the ends of the bone. It is hoped this discovery will lead to lowering the amount of bone marrow needed for a donation while increasing regeneration and lessening rejection in the recipient patients, says principal investigator Mick Bhatia, professor and scientific director of the McMaster Stem Cell and Cancer Research Institute. In a paper published online today by the journal Cell ...

Bacteria hold the clues to trade-offs in financial investments and evolution

2013-08-01
Scientists have found that bacteria have the potential to teach valuable investment lessons. The research, published in the journal Ecology Letters, takes advantage of the fact that bacteria, like humans, have limited resources and are constantly faced with investment decisions. Bacteria though are successful with their investments and have colonised every inch of the surface of our planet. The researchers, from the Universities of Exeter and Sydney, used mathematical models and lab-based synthetic biology, to predict bacterial investment crashes and boom-bust cycles. ...

UC San Diego researchers develop efficient model for generating human iPSCs

2013-08-01
Researchers at the University of California, San Diego School of Medicine report a simple, easily reproducible RNA-based method of generating human induced pluripotent stem cells (iPSCs) in the August 1 edition of Cell Stem Cell. Their approach has broad applicability for the successful production of iPSCs for use in human stem cell studies and eventual cell therapies. Partially funded by grants from the California Institute for Regenerative Medicine (CIRM) and the National Institutes of Health (NIH), the methods developed by the UC San Diego researchers dramatically ...

Fly study finds 2 new drivers of RNA editing

2013-08-01
PROVIDENCE, R.I. [Brown University] — RNA editing gives organisms a way to adapt the instructions that their DNA provides for making proteins. Few people would have described RNA editing as a simple process, but a new paper in Nature Communications demonstrates the process as more complex and difficult to predict than previously assumed. The study, done in living fruit flies, discovered two new mechanisms that govern editing in a key neurodevelopmental gene. RNA editing is governed not only by sequences of RNA nucleotides (the letters A, C, G, and U) and corresponding ...

Ultrasound patch heals venous ulcers in human trial

2013-08-01
In a small clinical study, researchers administered a new method for treating chronic wounds using a novel ultrasound applicator that can be worn like a band-aid. The applicator delivers low-frequency, low-intensity ultrasound directly to wounds, and was found to significantly accelerate healing in five patients with venous ulcers. Venous ulcers are caused when valves in the veins malfunction, causing blood to pool in the leg instead of returning to the heart. This pooling, called venous stasis, can cause proteins and cells in the vein to leak into the surrounding tissue ...

New designer compound treats heart failure by targeting cell nucleus

2013-08-01
Researchers from Case Western Reserve University School of Medicine and the Dana-Farber Cancer Institute have made a fundamental discovery relevant to the understanding and treatment of heart failure – a leading cause of death worldwide. The team discovered a new molecular pathway responsible for causing heart failure and showed that a first-in-class prototype drug, JQ1, blocks this pathway to protect the heart from damage. In contrast to standard therapies for heart failure, JQ1 works directly within the cell's command center, or nucleus, to prevent damaging stress responses. ...

When galaxies switch off

2013-08-01
Some galaxies hit a point in their lives when their star formation is snuffed out, and they become "quenched". Quenched galaxies in the distant past appear to be much smaller than the quenched galaxies in the Universe today. This has always puzzled astronomers -- how can these galaxies grow if they are no longer forming stars? A team of astronomers has now used a huge set of Hubble observations to give a surprisingly simple answer to this long-standing cosmic riddle. Until now, these small, snuffed-out galaxies were thought to grow into the larger quenched galaxies we ...

Nice organisms finish first: Why cooperators always win in the long run

2013-08-01
Leading physicists last year turned game theory on its head by giving selfish players a sure bet to beat cooperative players. Now two evolutionary biologists at Michigan State University offer new evidence that the selfish will die out in the long run. "We found evolution will punish you if you're selfish and mean," said lead author Christoph Adami, MSU professor of microbiology and molecular genetics. "For a short time and against a specific set of opponents, some selfish organisms may come out ahead. But selfishness isn't evolutionarily sustainable." The paper "Evolutionary ...

Potential nutritional therapy for childhood neurodegenerative disease

2013-08-01
Researchers at the University of California, San Diego School of Medicine have identified the gene mutation responsible for a particularly severe form of pontocerebellar hypoplasia, a currently incurable neurodegenerative disease affecting children. Based on results in cultured cells, they are hopeful that a nutritional supplement may one day be able to prevent or reverse the condition. The study, from a team of international collaborators led by Joseph G. Gleeson, MD – Howard Hughes Medical Institute investigator and professor in the UCSD Departments of Neurosciences ...

LAST 30 PRESS RELEASES:

Multi-resistance in bacteria predicted by AI model

Tinker Tots: A citizen science project to explore ethical dilemmas in embryo selection

Sensing sickness

Cost to build multifamily housing in California more than twice as high as in Texas

Program takes aim at drinking, unsafe sex, and sexual assault on college campuses

Inability to pay for healthcare reaches record high in U.S.

Science ‘storytelling’ urgently needed amid climate and biodiversity crisis

KAIST Develops Retinal Therapy to Restore Lost Vision​

Adipocyte-hepatocyte signaling mechanism uncovered in endoplasmic reticulum stress response

Mammals were adapting from life in the trees to living on the ground before dinosaur-killing asteroid

Low LDL cholesterol levels linked to reduced risk of dementia

Thickening of the eye’s retina associated with greater risk and severity of postoperative delirium in older patients

Almost one in ten people surveyed report having been harmed by the NHS in the last three years

Enhancing light control with complex frequency excitations

New research finds novel drug target for acute myeloid leukemia, bringing hope for cancer patients

New insight into factors associated with a common disease among dogs and humans

Illuminating single atoms for sustainable propylene production

New study finds Rocky Mountain snow contamination

Study examines lactation in critically ill patients

UVA Engineering Dean Jennifer West earns AIMBE’s 2025 Pierre Galletti Award

Doubling down on metasurfaces

New Cedars-Sinai study shows how specialized diet can improve gut disorders

Making moves and hitting the breaks: Owl journeys surprise researchers in western Montana

PKU Scientists simulate the origin and evolution of the North Atlantic Oscillation

ICRAFT breakthrough: Unlocking A20’s dual role in cancer immunotherapy

How VR technology is changing the game for Alzheimer’s disease

A borrowed bacterial gene allowed some marine diatoms to live on a seaweed diet

Balance between two competing nerve proteins deters symptoms of autism in mice

Use of antifungals in agriculture may increase resistance in an infectious yeast

Awareness grows of cancer risk from alcohol consumption, survey finds

[Press-News.org] We each live in our own little world -- smellwise