PT - JOURNAL ARTICLE AU - Olga Taryma-Lesniak AU - Katarzyna Ewa Sokolowska AU - Tomasz Kazimierz Wojdacz TI - Short history of 5-methylcytosine: from discovery to clinical applications AID - 10.1136/jclinpath-2020-206922 DP - 2021 Jan 11 TA - Journal of Clinical Pathology PG - jclinpath-2020-206922 4099 - http://jcp.bmj.com/content/early/2021/01/11/jclinpath-2020-206922.short 4100 - http://jcp.bmj.com/content/early/2021/01/11/jclinpath-2020-206922.full AB - Covalent modifications of nucleotides in genetic material have been known from the beginning of the last century. Currently, one of those modifications referred to as DNA methylation, is impacting personalised medicine both as a treatment target and a biomarker source for clinical disease management. In this short review, we describe landmark discoveries that led to the elucidation of the DNA methylation importance in the cell’s physiology and clarification of its role as one of the major processes in disease pathology. We also describe turning points in the development of methodologies to study this modification, which ultimately resulted in the development of in-vitro diagnostic kits targeting disease related DNA methylation changes as biomarkers.