RESUMO
A gene is the molecular unit of heredity of a living organism. A gene is said to be polymorphic if multiple allele occupies that gene’s locus within a given population. Tumor necrosis factor (TNF) is a pro-inflammatory adipokine involved in systemic inflammation and arouse acute phase reaction. Large amounts of TNF-α are released in response to lipopolysaccharides, other bacterial products, and Interleukin-1 (IL-1). TNF-α maps to chromosome 6p21.3, spans to about 3 kilobases and contains 4 exons. Single nucleotide polymorphisms (SNP) in the gene encoding TNF α are largely studied. Transcription activity and levels of TNF-α is dependent on the single nucleotide polymorphisms at the various intron and exon positions. This article sheds light on the many conditions associated with TNF-α polymorphism in relation to periodontitis and other systemic diseases in brief.