Featured Research

from universities, journals, and other organizations

Variability in olfactory receptors affects human odor perception

Date:
December 8, 2013
Source:
Monell Chemical Senses Center
Summary:
Researchers have found that as much as 30 percent of the large array of human olfactory receptor differs between any two individuals. This substantial variation is in turn reflected by variability in how each person perceives odors.

Using sophisticated mathematical modeling to extrapolate results, researchers predict that the olfactory receptors of any two individuals differ by about 30 percent. This means that for any two randomly chosen individuals, approximately 140 of their 400 olfactory receptors will differ in how they respond to odor molecules.
Credit: Claudio Divizia / Fotolia

According to Gertrude Stein, "A rose is a rose is a rose," but new research indicates that might not be the case when it comes to the rose's scent. Researchers from the Monell Center and collaborating institutions have found that as much as 30 percent of the large array of human olfactory receptor differs between any two individuals. This substantial variation is in turn reflected by variability in how each person perceives odors.

Humans have about 400 different types of specialized sensors, known as olfactory receptor proteins, that somehow work together to detect a large variety of odors.

"Understanding how this huge array of receptors encodes odors is a challenging task," says study lead author Joel Mainland, PhD, a molecular biologist at Monell. "The activation pattern of these 400 receptors encodes both the intensity of an odor and the quality -- for example, whether it smells like vanilla or smoke -- for the tens of thousands of different odors that represent everything we smell. Right now, nobody knows how the activity patterns are translated into a signal that our brain registers as the odor."

Adding to the complexity of the problem, the underlying amino acid sequence can vary slightly for each of the 400 receptor proteins, resulting in one or more variants for each of the receptors. Each receptor variant responds to odors in a slightly different way and the variants are distributed across individuals such that nearly everyone has a unique combination of olfactory receptors.

To gain a better understanding of the extent of olfactory receptor variation and how this impacts human odor perception, Mainland and his collaborators used a combination of high-throughput assays to measure how single receptors and individual humans respond to odors. The results, published in Nature Neuroscience, provide a critical step towards understanding how olfactory receptors encode the intensity, pleasantness and quality of odor molecules.

The researchers first cloned 511 known variants of human olfactory receptors and embedded them in host cells that are easy to grow in the laboratory. The next step was to measure whether each receptor variant responded to a panel of 73 different odor molecules. This process identified 28 receptor variants that responded to at least one of the odor molecules.

Drilling down, the researchers next examined the DNA of 16 olfactory receptor genes, discovering considerable variation within the genes for discrete receptors.

Using sophisticated mathematical modeling to extrapolate from these results, Mainland predicts that the olfactory receptors of any two individuals differ by about 30 percent. This means that for any two randomly chosen individuals, approximately 140 of their 400 olfactory receptors will differ in how they respond to odor molecules.

To understand how variation in a single olfactory receptor affects odor perception, the researchers studied responses to odors in individuals having different variants of a receptor known as OR10G4. They found that variations in the OR10G4 receptor were related to how people perceive the intensity and pleasantness of guaiacol, a molecule that often is described as having a 'smoky' characteristic.

Moving forward, a current study is relating the olfactory receptor repertoire of hundreds of people with how those people respond to odors. The data will enable the researchers to identify additional examples of how changes in individual receptors affect olfactory perception.

"The long-term goal is to figure out how the receptors encode odor molecules well enough that we can actually create any odor we want by manipulating the receptors directly," said Mainland. "In essence, this would allow us to 'digitize' olfaction."


Story Source:

The above story is based on materials provided by Monell Chemical Senses Center. Note: Materials may be edited for content and length.


Journal Reference:

  1. Joel D Mainland, Andreas Keller, Yun R Li, Ting Zhou, Casey Trimmer, Lindsey L Snyder, Andrew H Moberly, Kaylin A Adipietro, Wen Ling L Liu, Hanyi Zhuang, Senmiao Zhan, Somin S Lee, Abigail Lin, Hiroaki Matsunami. The missense of smell: functional variability in the human odorant receptor repertoire. Nature Neuroscience, 2013; DOI: 10.1038/nn.3598

Cite This Page:

Monell Chemical Senses Center. "Variability in olfactory receptors affects human odor perception." ScienceDaily. ScienceDaily, 8 December 2013. <www.sciencedaily.com/releases/2013/12/131208133402.htm>.
Monell Chemical Senses Center. (2013, December 8). Variability in olfactory receptors affects human odor perception. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2013/12/131208133402.htm
Monell Chemical Senses Center. "Variability in olfactory receptors affects human odor perception." ScienceDaily. www.sciencedaily.com/releases/2013/12/131208133402.htm (accessed July 29, 2014).

Share This




More Mind & Brain News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Losing Sleep Leaves You Vulnerable To 'False Memories'

Losing Sleep Leaves You Vulnerable To 'False Memories'

Newsy (July 27, 2014) A new study shows sleep deprivation can make it harder for people to remember specific details of an event. Video provided by Newsy
Powered by NewsLook.com
University Quiz Implies Atheists Are Smarter Than Christians

University Quiz Implies Atheists Are Smarter Than Christians

Newsy (July 25, 2014) An online quiz from a required course at Ohio State is making waves for suggesting atheists are inherently smarter than Christians. Video provided by Newsy
Powered by NewsLook.com
Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins