Specific AnosmiasNCT00220038
Experiments to Test How and Why the Sense of Smell Differs Between People
An observational study of Specific Anosmias, run by Rockefeller University at 1 site in United States.
Trial summary
The ability to smell varies greatly between different individuals. Some people are unable to detect an odor that most people can smell. It is not known what causes these individual differences. Humans have about 1000 genes for odorant receptors that bind and detect odor molecules. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Specific Anosmias
- What is being tested?
- smell tests
- Type of treatment
- Lifestyle or therapy programme
- How many people
- 500 participants
- Where
- 1 siteUnited States
- Study dates
- May 2004to May 2010
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: 700 healthy normal volunteers will be recruited from the New York City area
Who may be able to join
- 18 years or older,
- Male and Female
- Normal sense of smell
- -
Who cannot join
- Not pregnant
- No history of nasal illness or surgery
- No seasonal allergies-
Trial locations and contacts
1 site in 1 country.
United States1 site
Rockefeller University Hospital
New York, New York, 10021
About this study
Official title: Genetic Basis of Specific Anosmias
The ability to smell varies greatly between different individuals. Some people are unable to detect an odor that most people can smell. It is not known what causes these individual differences. Humans have about 1000 genes for odorant receptors that bind and detect odor molecules. It has been shown that some of these genes exist in two forms: a functional one and one that has been mutated and is therefore no longer functional. We think that people who can not smell a specific odor may carry the non-functional form of the gene for the receptor that detects the odor molecule. To test this hypothesis we want to find people who can not detect a specific smell and then compare their odorant receptor genes with those of people who can smell the odor.
Read the detailed description
The enjoyment of a fine wine, the odor of a ripe cheese, the memory of a long-lost grandmother brought back by the scent of her perfume, or the alarm we feel when we smell smoke are all produced by a functioning olfactory system. Interestingly, there are enormous individual differences in how we interpret these smells. Given almost any odor, some people will find it pleasant, others unpleasant. Ripe cheese or garlic may smell delicious to some, but repulsive to others. The scientific basis of this variation has not been well-studied. Despite the clear evidence for culture-based preferences for food and aromas, the nature-versus-nurture debate for smell remains unresolved. We believe there may be a genetic basis for our unique senses of smell. For example, some of us can smell methanethiol, the metabolite that is excreted in our urine after eating asparagus, whereas other people cannot. The Rockefeller University Smell Study seeks to recruit 400 normal subjects to track down the genetic basis of how we perceive smells. The study consists of up to two visits, each lasting up to 4 hours, in which we will test your perception of a variety of smells. On your first visit there will be a small blood sample taken (8.5 millileters) and your height and weight will be measured. If you are a woman of child-bearing age, we will ask you to provide a urine sample to test for pregnancy. If you are pregnant, you will not be permitted to participate in our study. You will fill out a short survey that asks some questions about yourself, your household, your personal habits, and your sense of smell. You will perform three different types of smell tests. In the first, you will be given two vials at a time and asked to tell us which contains an odor. In the second type of test, you will be asked to describe carefully your impression of three different odors. In the third type of test, you will be asked to rate odors according to their strength and pleasantness. All odorants will be presented to you in glass jars. You will be asked to smell odors in several hundred jars.
- Conditions
- Specific Anosmias
- Being tested
- smell tests
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
smell testsBehavioural
subjects are instructed to sniff two vials, one containing the solvent, the other a dilution of the odorant. They are asked to scan the vial with the stronger odor.
| Study group | Role | What they receive |
|---|---|---|
| Normal | 700 healthy adult volunteers will be drawn from the New York City area Receives: Behavioral: smell tests |
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Sep 2005 (estimated)
- Study startMay 2004
- Primary completionJan 2007
- Study completionMay 2010
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Specific AnosmiasStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 500 participants (actual)
Sponsor and investigators
- Lead sponsor
- Rockefeller University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Leslie B. Vosshall, PHD, Principal investigator, Rockefeller University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00220038
- Sponsor's protocol ID
- LVO-0539
- Status last verified
- Jan 2012
- First submitted
- 21 Sep 2005
- Last updated
- 11 Jan 2012
- Results posted
- No
- Data monitoring committee
- No
Study at a glance
From the registry record, last updated by the sponsor on 11 Jan 2012. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Genetic Basis of Specific Anosmias
- ClinicalTrials.gov ID
- NCT00220038
- Acronym / sponsor ID
- LVO-0539
- Conditions
- Specific Anosmias
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 500 participants (actual)
- Lead sponsor
- Rockefeller UniversityUniversity, hospital or other
- Study start
- May 2004
- Primary completion
- Jan 2007 (actual)
- Study completion
- May 2010 (actual)
- First posted
- 22 Sep 2005 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The ability to smell varies greatly between different individuals. Some people are unable to detect an odor that most people can smell. It is not known what causes these individual differences. Humans have about 1000 genes for odorant receptors that bind and detect odor molecules. It has been shown that some of these genes exist in two forms: a functional one and one that has been mutated and is therefore no longer functional. We think that people who can not smell a specific odor may carry the non-functional form of the gene for the receptor that detects the odor molecule. To test this hypothesis we want to find people who can not detect a specific smell and then compare their odorant receptor genes with those of people who can smell the odor.
Detailed description
The enjoyment of a fine wine, the odor of a ripe cheese, the memory of a long-lost grandmother brought back by the scent of her perfume, or the alarm we feel when we smell smoke are all produced by a functioning olfactory system. Interestingly, there are enormous individual differences in how we interpret these smells. Given almost any odor, some people will find it pleasant, others unpleasant. Ripe cheese or garlic may smell delicious to some, but repulsive to others. The scientific basis of this variation has not been well-studied. Despite the clear evidence for culture-based preferences for food and aromas, the nature-versus-nurture debate for smell remains unresolved. We believe there may be a genetic basis for our unique senses of smell. For example, some of us can smell methanethiol, the metabolite that is excreted in our urine after eating asparagus, whereas other people cannot. The Rockefeller University Smell Study seeks to recruit 400 normal subjects to track down the genetic basis of how we perceive smells. The study consists of up to two visits, each lasting up to 4 hours, in which we will test your perception of a variety of smells. On your first visit there will be a small blood sample taken (8.5 millileters) and your height and weight will be measured. If you are a woman of child-bearing age, we will ask you to provide a urine sample to test for pregnancy. If you are pregnant, you will not be permitted to participate in our study. You will fill out a short survey that asks some questions about yourself, your household, your personal habits, and your sense of smell. You will perform three different types of smell tests. In the first, you will be given two vials at a time and asked to tell us which contains an odor. In the second type of test, you will be asked to describe carefully your impression of three different odors. In the third type of test, you will be asked to rate odors according to their strength and pleasantness. All odorants will be presented to you in glass jars. You will be asked to smell odors in several hundred jars.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Normal | – | Behavioral: smell tests700 healthy adult volunteers will be drawn from the New York City area |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- 700 healthy normal volunteers will be recruited from the New York City area
Key inclusion criteria (4 listed)
- 18 years or older,
- Male and Female
- Normal sense of smell
- -
Key exclusion criteria (3 listed)
- Not pregnant
- No history of nasal illness or surgery
- No seasonal allergies-
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| smell testssubjects are instructed to sniff two vials, one containing the solvent, the other a dilution of the odorant. They are asked to scan the vial with the stronger odor. | Behavioural | Normal |
Primary outcome
Not reported in the source record.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 11 Jan 2012.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Leslie B. Vosshall, PHD principal investigator
Rockefeller University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Specific Anosmias, run by Rockefeller University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 11 Jan 2012. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Jan 2012; AzTrials last refreshed its copy on 7 Nov 2026.