IL1A and periodontitis: A hypothesis has been made to explain the role of infectogenomics in perio- systemic relationship mainly in type 2 diabetes mellitus in association with IL-1 genotype polymorphisms and suggested that dental plaque remains the major contributory factor to progressive periodontitis with periodontal interleukin-1 gene polymorphisms and differences in oral microbiota seem to play only a subordinate role [79].