Take out the genetic code DNA, and we will become strangers. Do you know that?/You know what? Do you know that?/You know what? The total amount of human genetic code is 3 times 10 to the ninth power, and a genetic code consists of four words. If every 3,000 words are typed and bound into a book, a person's genetic code is 6,543.8+0,000 pages. If a book is bound every 100 page, our genetic code can be packaged into 10000 page. Taking tumors as an example, it is generally considered that treatment is difficult. There is another very important reason. Our genetic code is 98% because we don't know its laws, so we don't consider the relationship between this part of the genetic code and diseases. If only 2% genetic code information is used as an indicator of tumor diagnosis, our analysis of tumor diseases will be inaccurate.

The genome is too computationally intensive and dynamic. This genetic code exists in a different development period from other tissues of the human body, indicating that it is big data. There are a lot of microorganisms in the human body. The importance of parasitic environment While studying our own genetic code, we should also study the genetic code of microorganisms that coexist with us. Epigenetics refers to the genetic change of gene expression when the nucleotide sequence of a gene remains unchanged. The analysis of epigenetic code is helpful to better understand and diagnose a series of diseases including cancer, so it has become an important direction of medical research.

The main method to crack the epigenetic code depends on a chemical called bisulfite. However, although the sequencing method based on this substance is useful, it also has many limitations. Most importantly, bisulfite will destroy most of the DNA it touches. There is not much sequencing data left after the modification. The new method developed by the University of Pennsylvania effectively overcomes this limitation. The researchers introduced a deaminase called apolipoprotein messenger RNA editing enzyme catalytic polypeptide (APOBEC). This DNA deaminase can effectively distinguish the modified state of cytochrome, which is similar to the effect of bisulfite, but it will not damage DNA.

Compared with bisulfite sequencing, the new method requires much less DNA input, only one thousandth of the last one. In the past, some epigenome studies were difficult to carry out because of insufficient samples, so the amount of DNA input required for sequencing was greatly reduced, which means that the application scope of sequencing will be expanded, which is helpful to promote such studies. The researchers said that the new method overcame many limitations of bisulfite-based sequencing methods, expanded the scope of epigenome analysis, and provided a new means for studying epigenetic codes. This is of great significance to further understand the complex biological processes such as nervous system development and tumor formation.