Analysis of genetic polymorphism and expression of SOX2 in oral leukoplakia: a case-control study

To investigate the association of SOX2 polymorphisms with oral leukoplakia with dysplasia (OLD) and compare it with the immunohistochemical expression of SOX-2.

The samples comprised 64 patients with oral leukoplakia and 20 with normal oral mucosa who were subjected to SOX2 polymorphism rs77677339 genotyping by real-time polymerase chain reaction and immunohistochemistry for SOX-2 (basal epithelium expression, suprabasal and total; nuclear area and intensity). Statistical tests included the Chi-square and Fisher's exact tests.

No significant difference was observed in genotype distribution between the OLD and control groups. The GG genotype (96.9%) was observed in the OLD group and 100% in the control group. The GA genotype was not observed in the control group. Statistical comparisons between the immunohistochemistry and genetic results were not statistically significant. No association was identified between rs77677339 and immunohistochemistry in OLD; however, the presence of allele A in heterozygotes with OLD suggests that this allele may serve as a risk marker.

The variant rs77677339 is localized in a region that contains different micro-RNA-binding sites, which can lead to changes in gene expression, contributing to OLD development through unclear molecular mechanisms. This study presents the preliminary results for this single nucleotide polymorphism in the literature.