Novel RNA extraction method from human tears

Document Type : Original article


1 Stem Cells Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran

2 Department of tissue engineering and cell therapy, School of Advanced Technology in Medicine, Shiraz University of Medical Sciences, Shiraz, Iran

3 Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran

4 Department of Medical Genetics, Shiraz University of Medical Sciences, Shiraz, Iran

5 Poostchi Ophthalmology Research Center, Department of Ophthalmology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran


Human tears can be used as a noninvasive source of genetic materials and biomarkers in the prognosis and diagnosis of ocular and non-ocular diseases. The present protocol is a novel direct RNA extraction method from tears. This study aims to provide a suitable method for direct extraction of RNA from tears with high quality and quantity. In this study, we develop a TRIzol base protocol for direct RNA extraction from human tears. quality and quantity of extracted RNA measured by calculation of 260/280 UV absorption ratio using Nanodrop and real-time PCR. RNA was extracted with this modified method and a purified (260/280 UV absorption ratio between 1.8 to 2 and a high yield of total RNA, on average 95 μg, from tears was extracted. In conclusion, we developed an easy and suitable method for direct extraction of total RNA from tears with high quality and quantity.


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