TOOTH DECAY: Genetics Plays a Role

The genetics of tooth decay is being revealed by scientists who are analyzing genes and dental health.

Dr. Mary L Marazita, who is the director of the Center for Craniofacial and Dental Genetics in the School of Dental Medicine at the University of Pittsburgh, is a leader in the field. She said the risk for tooth decay is about 60 percent due to genetic factors.

The take-home message from this is that if someone from a family with bad teeth must be even more vigilant in dental hygiene than those in a family without bad teeth. Also, it might be wise to purchase dental insurance.

Genetic dentistry has not been developing in line with general medical genetics, but is a relatively new field. Progress has been made, however. One of the significant discoveries is that some gene variants are associated with “sweet preference,” and people with the gene variant for sweet preference will be more likely to develop tooth decay.

Tooth enamel, the outer covering of the teeth, is important in determining whether one with have problems with their teeth. Softer enamel means that bacteria will more easily be able to get into the inner space of the teeth and cause decay. Some genes contribute to having softer or harder tooth enamel.

A recent development in the study of the genetics of tooth decay is an association with the ability to taste certain tastes. For example, some people can taste cilantro and enjoy the flavor. Other people find the flavor to be horrible and have described it as “licking soap.” 

A study from Monell Chemical Senses Center and published in the September 13, 2012, issue of the Oxford Journal looked at the genetics of taste . It showed that some people have genes that confer the ability to taste a particular substance but other people have genetic variants that do not allow them to sense the same flavor.

Some people have a greater range in ability to perceive tastes compared to others. The studies on the genetics of dental health have shown that the greater variety one has in ability to sense different tastes the less likely they will develop tooth decay. Whether that comes from a genetic basis or is due to enjoying a more expanded sense of taste, meaning one eats fewer sweets, is yet to be determined.

The genes one inherits for saliva plays a role in the proclivity towards developing tooth decay. Another major component that determines how prone one is to tooth decay is bacteria and the immune system. The mouth is full of bacteria and no amount of mouthwash will get rid of all of it. The bacterial community in the mouth is large and diverse. The immune system keeps the bacterial growth in check and the genes one inherits for the immune system determines how well the bacteria are kept under control.

If 60 percent of the risk for developing tooth decay comes from genetic factors, this means 40 percent of the risk comes from environmental factors. The environmental factors include dental hygiene and diet. Sugary drinks are the biggest culprit in setting one up for tooth problems. Alcoholic drinks have not been shown to affect risk for tooth decay. Fluoride has been shown to be helpful in protecting against tooth decay.