“…Elevated serum TNF-α levels have been observed in OLP patients compared to healthy controls [ 11 ]. So far, several single nucleotide polymorphisms (SNPs) within the promoter sequence (-238, -244, -308, -376, -489, -575, -610, -851, -857, -863, -1031) of the TNF-α gene have been reported that affect transcriptional regulation and therefore susceptibility of different diseases [ 19 , 20 ]. The SNP that occurs in the regulatory position − 1031, the promoter of the TNF-α gene, is characterized by the substitution of cytosine for thymine [ 21 ].…”