Study of Taste Deficits

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.

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Key information

Conditions

Taste Disorder Healthy Nervous System Diseases Neurologic Manifestations Pathological Conditions, Signs and Symptoms Sensation Disorders Signs and Symptoms Taste Disorders

Age range

18 year and older

Sex eligibility

All sexes

Study type

Observational

Primary location

National Institutes of Health Clinical Center, 9000 Rockville Pike

Bethesda, Maryland, 20892, United States

About this study

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.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

INCLUSION CRITERIA:
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.

Exclusion 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

Sponsors and collaborators

Lead sponsor

National Institute on Deafness and Other Communication Disorders (NIDCD)

Nih

Registry information

Official study title

Studies of Deficits in the Sense of Taste

Important dates

Study start: 2001
Study completion: 2019
First posted: Aug 20, 2001
Registry last updated: Jun 6, 2019

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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