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Study of Taste Deficits

This study is currently recruiting participants. (see Contacts and Locations)
Verified April 3, 2017 by National Institutes of Health Clinical Center (CC)
Information provided by (Responsible Party):
National Institutes of Health Clinical Center (CC) ( National Institute on Deafness and Other Communication Disorders (NIDCD) ) Identifier:
First received: August 17, 2001
Last updated: April 20, 2017
Last verified: April 3, 2017

This study will explore the genetics of taste and taste deficits. The sense of taste plays a crucial role in food choices, allowing people to identify beneficial foods (those with high caloric value, which are typically sweet) and foods likely to be toxic (usually bitter substances). The loss of sense of taste in older people plays a role in decreased appetite and poor nutrition. Taste deficits may adversely affect people in ways that are not well understood. This study will examine why some people (about one-fourth of all people in the United States) cannot taste a substance called phenylthiocarbamide (PTC). The inability to taste PTC is due to inherited factors that are not yet clear.

Individuals age 18 and older who can taste PTC and individuals who cannot taste PTC may be eligible for this study. Participants will taste a number of liquid solutions until they find one with a clear taste. Then they will taste another group of solutions and decide which ones have that taste and which have no taste. Finally, they will taste a third group of solutions until they find one with a different taste. About 2 tablespoons of blood will be drawn from participants for genetic tests related to the sense of taste.

Taste Disorder

Study Type: Observational
Official Title: Studies of Deficits in the Sense of Taste

Resource links provided by NLM:

Further study details as provided by National Institutes of Health Clinical Center (CC):

Estimated Enrollment: 600
Study Start Date: August 15, 2001
Detailed Description:
The primary goal of this study is to identify the underlying cause of deficits in the ability to taste different commonly consumed substances, including the bitter compound phenylthiocarbamide (PTC) as a model. Individuals will be tested to identify those who can and cannot taste PTC, as well as for their ability to taste a variety of sweet, sour, salty, and savory substances. Individuals will have 20 cc of blood drawn to obtain DNA. These DNA samples will then be analyzed for variation in genes whose products are known to be involved in taste perception pathways. Information about individuals DNA sequence variation will then be correlated with their taste phenotype to identify the specific genetic variation that causes phenotypic variation, providing molecular structure-function information in taste sensory pathways.

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
  • Individuals age 18 years and older.
  • Subjects must be medically healthy, with no cognitive impairment or physical swallowing inability or impairment
  • Must be able to provide informed consent
  • Must be able to read and understand English.
  • NIH employees or staff may participate in this study if they meet the eligibility criteria.


  • Cannot be younger than 18 years of age
  • Subjects with suspected or known cognitive impairment or physical swallowing inability or impairment
  • Subjects who are unable to provide informed consent
  • Subjects who are taking any pyschoactive medications or medications that affect their nervous system, such as antidepressants or anti-psychotics.
  • Subjects who have known problems with these sense of taste
  • Subjects who are currently using tobacco
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00022997

Contact: Dennis T Drayna, Ph.D. (301) 402-4930

United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike Recruiting
Bethesda, Maryland, United States, 20892
Contact: For more information at the NIH Clinical Center contact Patient Recruitment and Public Liaison Office (PRPL)    800-411-1222 ext TTY8664111010   
Sponsors and Collaborators
National Institute on Deafness and Other Communication Disorders (NIDCD)
Principal Investigator: Dennis T Drayna, Ph.D. National Institute on Deafness and Other Communication Disorders (NIDCD)
  More Information

Additional Information:
Responsible Party: National Institute on Deafness and Other Communication Disorders (NIDCD) Identifier: NCT00022997     History of Changes
Other Study ID Numbers: 010230
Study First Received: August 17, 2001
Last Updated: April 20, 2017

Keywords provided by National Institutes of Health Clinical Center (CC):
Population Associations
Healthy Volunteer
Normal Control

Additional relevant MeSH terms:
Taste Disorders
Sensation Disorders
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms processed this record on April 26, 2017