hsa-mir-3681: Hsa-mir-3681 is a microRNA derived from an LTR element and located on the p arm of human chromosome 2 [PMC7398795]. Although it has not been extensively studied, dysregulation of hsa-mir-3681 has been reported in human disease and cancer, with downregulation observed in cervical cancer [PMC7398795]. The seed region of hsa-mir-3681-5p is 5′-AGUGGAU-3′ [PMC7398795]. The enhancer activity of hsa-mir-3681 has been shown to be associated with VNTRs (Variable Number Tandem Repeats) [PMC7398795]. In luciferase assays, the presence of hsa-mir-3681 mimic and hsa-mir-3681-5p inhibitor resulted in upregulation of luciferase activity [PMC7398795]. Interestingly, when used together, the enhancer activity was enhanced even more compared to when only the hsa-mir-3681 mimic was used alone [PMC7398795]. The enhancer activity of SHISA7, with three and six 9-mer hsa-mir-3681 binding regions, was found to be in cooperation with transcription factors (TFs) based on examination using TRANSFAC v8.0 [PMC7398795]. Hsa-mir-3681 overlaps with LTR16D1 [PMC7398795]. Further studies are needed to confirm whether the enhancer activity observed is contributed by VNTRs or TFs [PMC7398795]. In conclusion, miRNA can affect VNTR by repressing its activity; however, in rare cases, VNTRs can gain enhancer activity by blocking hsa-mir-3681 mimics using a hsa-miR‑368‑3p inhibitor [PMC7398795]. The enhancer activity of hsa-mir-3681-5p binding primers was observed in the presence of hsa-mir-3681 mimic treatment [PMC7398795].