MTHFR and cervical intraepithelial neoplasia: Therefore, the present study was designed to evaluate the C677T and A1298C mutations of MTHFR gene in cervical intraepithelial neoplasia (CIN) related to HPVs subjects and most common sexually transmitted pathogens such as Chlamydia trachomatis, HSV-2 and Mycoplasma genitalium in Iranian women suffering from STI coinfections.