The beginning

A common question that may come to mind when you hear the word "epigenetics" for the first time is: Where does this word actually come from? The history of epigenetics is closely linked to the research of evolution and development [1]. The term was originally in 1942 by the embryologist Dr. Waddington shaped and derives from the Greek word "epigenesis", which originally described the influence of genetic processes on the development [2]. Although the term only appeared in the 1940s, the "Epi" in "Epigenetics" can be traced back to the 19th century - the idea that genes are influenced by factors that go beyond the genome [3].

Late 20th century

Until the 1950s, the word "epigenetics" was inaccurate to include all development events, from the fertilized cygote to the adult organism [1]. At that time, Waddington proposed the famous "epigenetic landscape". He described the cell as a ball that was able to go different paths due to the uneven surface, which symbolized intra- and extracellular environmental influences [4].

From 1970 to 1980, the identification of High Mobility Group (HMG) proteins enabled scientists to recognize that in addition to histones (which were discovered at the beginning of the 20th century) there are also other proteins that play a role in phenotype expression and in the chromatin architecture [5]. This was followed by the discovery of the phenomenon of the shaped genes and its regulation according to the maternal and paternal inheritance [6].

Nevertheless, the DNA methylation (5MC) and post-translational histone modifications were identified shortly after the DNA double helix structure. The DNA methylation was discovered early, in 1965. Other modifications such as histone methylation, acetylation, phosphorylation, ubiquitylation, sumoylation and ADP ribosylation were discovered between 1962 and 1977 [8,9].

Early 21st century

Despite the fact that a lot was understood about the DNA and its general organization in the middle of the last century, epigenetics was only intensively researched in the 1990s and 2000s. Advances in the field of cloning (e.g. dolly the sheep) contributed to answering several unanswered questions [7]. The development of tool boxes and biochemical techniques enabled researchers to identify specific enzymes, readers, writers and erasers from epigenetic markings.

Present

To date, DNA methylation is one of the best-examined and best characterized epigenetic modifications. An example of the importance of this process and its biological relevance is X-Inmertivation. This is a process in which one of the two X chromosomes is inactivated in female mammals. The inactive X-chromosome is closed and packed in heterochromatin, a structure that is transcriptionally inactive [10]. The decommissioning is therefore carried out due to the high degree of DNA methylation, accompanied by other histone modifications [11].

The path to a complete understanding of the importance of epigenetics is long. Nevertheless, there is still a lot to discover in this relatively new and exciting study area. At Moleqlar Analytics, our goal is to contribute to deepening the knowledge of our epigenetic code, validating biomarkers of different diseases and identifying new epigenetic drugs. In the near future, Moleqlar Analytics would like to leave a remarkable footprint in this area.