Decoding the Phenylthiocarbamide Tasting Puzzle: Diagnosis and Genetic Testing

Expert Reviewed By: ⁠Dr. Brandon Colby MD

Phenylthiocarbamide (PTC) tasting is a genetic trait that allows certain individuals to taste the bitter compound phenylthiocarbamide. This intriguing ability has been the subject of numerous studies to better understand the genetic factors behind it and its possible implications on health. In this article, we will delve into the process of understanding, diagnosing, and using genetic testing for phenylthiocarbamide tasting.

Understanding Phenylthiocarbamide Tasting

PTC tasting is a classic example of a genetic trait with a simple Mendelian inheritance pattern. This means that the ability to taste PTC is determined by a single gene with two possible alleles: a dominant allele for tasting (T) and a recessive allele for non-tasting (t). Individuals with at least one dominant allele (TT or Tt) can taste PTC, while those with two recessive alleles (tt) cannot.

Several studies have been conducted to explore the prevalence and variability of PTC tasting in different populations. For example, a study on the Bagatha tribes in India examined taste sensitivity to PTC and colorblindness, while another study on the Osing population in Kemiren-Banyuwangi investigated the prevalence, gene frequency, and genotype frequency of PTC tasting ability. Both studies, along with others, contribute to the growing body of knowledge on the genetic factors behind PTC tasting.

Diagnosing Phenylthiocarbamide Tasting

Phenylthiocarbamide tasting can be diagnosed using a simple taste test. In this test, a small amount of PTC is applied to a piece of paper or a cotton swab, which is then placed on the individual’s tongue. Those who can taste PTC will experience a strong, bitter taste, while non-tasters will not perceive any taste or only a very mild taste.

It is important to note that the ability to taste PTC is not an all-or-nothing trait. Some individuals may be more sensitive to PTC than others, which could be influenced by factors such as age, sex, and genetic background. For example, a study on the Manipuri Muslim population found variability in PTC taste sensitivity among males and females.

Uses of Genetic Testing for Phenylthiocarbamide Tasting

Genetic testing can be helpful in confirming the presence of the PTC tasting gene and providing a more accurate assessment of an individual’s PTC tasting ability. This can be particularly useful in cases where the taste test results are unclear or inconclusive. Genetic testing can also provide insights into the inheritance pattern of PTC tasting within a family and help predict the likelihood of offspring inheriting the trait.

Health Implications of Phenylthiocarbamide Tasting

While PTC tasting may seem like a trivial trait, it has been suggested that the ability to taste PTC could be related to other genetic traits and health conditions. For example, a study on Iraqi adults explored the possible relation among PTC tasting ability, earlobes attachment, tongue rolling ability, and dental malocclusion.

Additionally, the ability to taste PTC has been linked to food preferences and dietary habits, which could have implications on overall health and nutrition. For instance, PTC tasters may be more sensitive to bitter-tasting compounds found in certain vegetables, which could influence their consumption of these nutrient-rich foods. Further research is needed to fully understand the health implications of PTC tasting and its potential role in disease prevention and management.

In conclusion, phenylthiocarbamide tasting is a fascinating genetic trait with potential implications on health and disease. Understanding, diagnosing, and using genetic testing for PTC tasting can provide valuable insights into this intriguing ability and contribute to the growing knowledge of human genetics and disease.

About The Expert Reviewer

Dr. Brandon Colby MD is a US physician specializing in the personalized prevention of disease through the use of genomic technologies. He’s an expert in genetic testing, genetic analysis, and precision medicine. Dr. Colby is also the Founder of  and the author of ⁠⁠Outsmart Your Genes.

Dr. Colby holds an MD from the Mount Sinai School of Medicine, an MBA from Stanford University’s Graduate School of Business, and a degree in Genetics with Honors from the University of Michigan. He is an Affiliate Specialist of the American College of Medical Genetics and Genomics (⁠⁠ACMG), an Associate of the American College of Preventive Medicine (⁠⁠ACPM), and a member of the National Society of Genetic Counselors (⁠NSGC)