Microorganisms are essential but not sufficient to cause periodontal disease which is multifactorial. It occurs due to the interplay of many factors, primarily microorganisms and host response. Recent technological breakthroughs have brought about a better understanding of many disease processess which highlight the role of genetic influences on their pathophysiology. The role of genes in modifying the host response and hence predisposition to and progression of periodontal diseases has been validated by recent research. The association of periodontal and systemic diseases can be better...