Contribution of Genetic Factors to Dental Caries Risk

Dental practioners found that there is a contribution of genetic factors to dental caries risk. They would find value in understanding the genetic contribution to caries risk for at least 2 reasons. First, they would be able to explain to patients that some forms of decay are more strongly associated with inherited risk. This would help explain for both the patient and dentist why persons with similar behavioral risks (ex- tooth brushing frequency or dietary habits) have different caries rates.

Dental caries is a multi factorial infectious disease, with many contributory environmental factors, there is also strong evidence for a genetic component in the etiology of this disease. With information from human genome and other related technologies like microbial genomics will provide contribution to both etiology and susceptibility to these diseases. Dental caries incidence is affected by host factors that may be related to the structure of dental enamel, immunologic response to cariogenic bacteria, or the composition of saliva.

Numerous reports have described a potential genetic contribution to the risk for dental caries. Studies of twins (studies by Neale and Cardon, 1992), families, and animal models have all indicated that caries has a genetic component. Evidence of a genetic contribution to caries is based on four questions examining inheritance that altered the dental hard tissues; the immune response; sugar metabolism & consumption; salivary flow, salivary constituents; & salivary defense systems.

There is increasing evidence that there are genetic risk factors relationships between dental caries and an individual’s phenotypic expression explaining that a gene defect directly altering the tooth structure and rendering it more susceptible to dental caries. Inherited disorders of tooth development with altered enamel structure increase the incidence of dental caries. Specific genetic linkage has not been determined for all of the syndromes of altered tooth development. Altered immune response to the cariogenic bacteria may also increase the incidence of caries.

Evidence supports the linkage of altered dental enamel development with increased susceptibility to dental caries. Increased enamel porosity, colonization of cariogenic bacteria. decreased mineral content, and the presence of enamel crystal inhibitory proteins all are directly linked to dental caries risk.Individual genes may provide multiple proteins, each with a different set of properties. The variation in proteins can contribute to the susceptibility for dental caries if a specific protein or a set of different proteins results in altering the host target, host immune response, or salivary interacting factors.

Moreover, information on the association of genetic markers spanning the whole genome with dental caries susceptibility and related phenotypes may actually become possible with the recent decoding of the human genome. Identification of genetic risk factors will help screen and identify susceptible patients to better understand the contribution of genes in caries aetiopathogenesis.

Information derived from these diverse studies will provide new tools to target individuals and/or populations for a more efficient and effective implementation.