Dr. Arne Schaefer, of the Institute for Clinical Molecular Biology, University of Kiel, Germany, said that they have discovered a genetic variant situated on chromosome 9, which was shared between the two diseases.
"We studied a genetic locus on chromosome 9p21.3 that had previously been identified to be associated with myocardial infarction, in a group of 151 patients suffering from the most aggressive, early-onset forms of periodontitis, and a group of 1097 CHD patients who had already had a heart attack," he said.
"The genetic variation associated with the clinical pictures of both diseases was identical," he added.
The further analysis of 1100 CHD patients and 180 periodontitis patients showed that the genetic risk variant is located in a genetic region that codes for an antisense DNA called ANRIL and that it is identical for both diseases.
Both CHD and periodontitis are propagated by the same risk factors - most importantly smoking, diabetes and obesity - and there is also a gender relationship, with men possibly more liable to these diseases than women.
"These factors already indicated a possible mutual genetic basis underlying the two diseases", said Schaefer.
"Now we know for sure that there is a strong genetic link, patients with periodontitis should try to reduce their risk factors and take preventive measures at an early stage.
"We hope that our findings will make it easier to diagnose the disease at an early stage, and that in future a greater insight into the specific pathophsyiology might open the way to effective treatment before the disease can take hold," he added.
The study was presented at the annual conference of the European Society of Human Genetics.