Nature Genetics: CfDNA whole gene predicts gene expression.

A study in the journal Nature Genetics shows that blood circulation free DNA (cfDNA) can provide clues to predict gene expression.
genome-wide sequencing to know whether genes express gene expression (gene expression) refers to the process by which cells transcribe and translate genetic information stored in THE DNA sequence, which is eventually converted into bioactive protein molecules.
to detect the level of gene expression, is qualitative or quantitative detection of the gene expression products, the most commonly used methods are semi-quantitative RT-PCR, fluorescent quantitative PCR, Northern blotting and so on.
now, scientists have found that the whole genome sequencing of cfDNA can be used to speculate on whether genes are expressed.
Austrian researchers have developed a way to detect gene expression using the read depth pattern of cfDNA.
the method is based on data from blood samples from hundreds of healthy individuals and applied to hundreds of cancer metastasis patients. "We use genome-wide sequencing data to determine gene expression, providing new insights into the cells that release cfDNA, and thus expanding existing cfDNA analysis methods," wrote Michael Speicher, senior author of the
and a researcher on human genetics at the University of Graz, Austria.
" the team points out that most of the cfDNA floating in the blood contains genetic material from apoptosis cells, such as dna in nucleosomes that still match protein complexes.
, the team concluded that it might be possible to reveal traces of nucleosomes associated with gene transcription activity through the long depth of cfDNA.
the researchers noted that the MNase test revealed that the gene transit starting point upstream, non-nuclear small body DNA can also be transcribed.
based on this, they first explored whether the initiator regions not occupied by the nucleosomes could be detected in cfDNA and, if possible, whether the markers could reflect the gene expression spectrum.
, the team expanded its analysis to look for expressions in the blood of cancer patients that could reveal cancer-driven genes.
179 blood samples from 50 healthy men and 54 healthy women, the researchers used Illumina's Miseq and Nextseq platforms for end-of-line sequencing to identify nucleonuclear DNA associated with nucleosomes in the plasma, and the resulting single-ended sequencing data could be used to evaluate long-read depth patterns near the transcription starting point, using existing MNase maps and THE FANAND5 gene expression data.
this information, in turn, can be used to develop algorithms for predicting gene expression based on the depth of cfDNA reading length.
by sequencing the blood-circulating free DNA of two breast cancer patients, the researchers obtained a gene expression spectrum and a number of copies, consistent with RNA sequencing data from primary tumor samples.
then, the researchers used the same method to study gene expression and copy number maps of 426 blood samples from other cancer patients, including metastatic colorectal, breast, lung or prostate cancer.
researchers point out that the method appears to be particularly promising for capturing cancer-driven genes, including the number of expressions and copies, but is not only useful for evaluating circulating tumor DNA in the environment of microresidual disease.
genetic information: As we all know, Japan is one of the world's most aging countries, according to the ministry last September released the latest statistics show that 20% of Japan's total population is now over 70 years old.
Japan is facing its biggest demographic crisis, even a national crisis, as its newborn birth rate hits record lows.
know that although Japan is the world's third largest economy, the population is only about 120 million, but because of the serious aging, has had to put more than a third of the national budget into the elderly, health care and other areas of people's livelihood.
it can be said that if the situation continues to deteriorate, Japan will face even greater pressure in the future.
of course, in the absence of a solution to the decline in the number of newborns, if it can delay the aging of the population, extend life expectancy, so that individuals work more hours, is also one of the important means to solve the population crisis.
, but also for "long life is not old", is also one of the goals of human pursuit.
recently, according to Japanese media reports, the University of Washington Professor Ichiro Ishii has discovered a longevity gene with the function of inhibiting aging.
said their study found that the longevity gene produces an enzyme that inhibits aging, which is found in everyone's body but loses its vitality as he gets older.
their research has also found the biomaterial NMN, which keeps these enzymes alive, and the substance has been effective in mice, with some products now on the market and the effects of their use being studied.
, according to some scientists, if the development of these anti-aging substances is successful, along with progress in organ replacement and biomechanical fusion research, humans may be close to life-long death by 2025.
as to the human life limit, according to the current scientific research, it is difficult to give accurate on-line.
, however, some U.S. researchers believe that the current predictable life expectancy of humans has not yet reached the limit, and will gradually increase.
therefore, it can be said that with scientific progress, the extension of human life has been a necessity.
and if a breakthrough in anti-aging can make, humans can even maintain a long-term younger state, which is to solve the aging of the population, reduce the burden of society, enhance social vitality is of great help.
at the same time, it may also enable humans to push their own physiological limits, to create more miracles.
of course, if this happens, human society will also face new problems, such as the Japanese media did an interesting survey, about 300 people surveyed believe that with the increase in life expectancy, by 2050 the japanese people's main cause of death may become suicide, longevity in some cases may also become a new burden.
Source: Decoding Medicine, Sohu.com.