Genetic and heritable risk factors in periodontal disease.

The purpose of this paper is to review current knowledge of genetic risk factors for the periodontal diseases and to present updated and additional data from the Minnesota Twin Periodontal Study. Family studies suggest that susceptibility to the early onset forms of disease, particularly prepubertal and juvenile periodontitis, is, at least in part, influenced by host genotype. Inherited phagocytic cell deficiencies appear to confer risk for prepubertal periodontitis. The prevalence and distribution of juvenile periodontitis in affected families are most consistent with an autosomal recessive mode of inheritance. However, considerable etiologic as well as genetic heterogeneity within these clinically-defined diseases is evident. Whether or not genetic factors influence the more common adult chronic periodontitis is less clear. Although results from family studies suggest that environmental factors appear to be the major determinants of variance in adult periodontitis, data from our twin studies indicate that both genetic and environmental factors influence disease. Furthermore, comparisons between reared-together and reared-apart adult monozygous twins indicate that early family environment has no appreciable influence on probing depth and attachment loss measures in adults.