Aurora magazine

Over 1300 scientists worked on the same project for 10 years: creating a genetic map of cancer. The results of this huge international work have been published in Nature, conquering the cover of the magazine. This is a fundamental discovery for the fight against cancer, which will allow the development of technologies for early diagnosis and new therapies.

The International Cancer Genome Consortium (Icgc) and the US consortium Tcga have joined together in an ambitious project: the Pan-Cancer Analysis of Whole Genomes (Pcawg). The researchers analyzed 2,600 genomes belonging to 38 tumor types, also analyzing areas neglected by previous studies.

Much of the genetic analysis of tumors focuses on 1% of the genome, that is, the one with the genes that code for proteins. This saves time and - above all - resources, but pushes to leave aside areas that could prove important. For this reason, the Pcawg has analyzed the genome as a whole, including the regions that regulate the ignition of genes.

The results confirmed the choice made: the regulation of the genes determines both the severity of the tumor and the responses to the various therapies. That's why, in the face of the same tumor, some people react better and others worse to the same drugs. In part it is because of the uniqueness of the patient. In part, however, contribute to the recurrent patterns present in all cancers of a certain type and a certain severity. By identifying these schemes, it is possible to predict which therapies will be most effective and to intervene immediately in the best way.

Source: repubblica.it

A new genetic editing technique has stopped the progression of a serious genetic disease in mice. The disease is the deficiency of ornithine transcarbamylase, a disease caused by hundreds of mutations in the same gene. Thanks to CRISPR, Penn Medicine scientists have developed a possible effective therapy on all mutations.

The authors of the study had already made an attempt at genetic therapy, but had managed to correct only one mutation. The approach had proven effective in newborn guinea pigs, but not in adults. This time, they developed a technique that inserts a mini-gene into the genome. The gene contains the correct information on how to code for the enzyme, in order to overwrite the wrong ones.

The new approach is effective on both puppies and adults. Above all, it is more effective than traditional cut and paste. In contrast to this, in fact, it manages to counteract a large number of mutations together. In this way, the organism resumes producing the enzyme and supporting it with the features that, without editing, would remain silent. The approach has proven effective on guinea pigs; scientists are working on the application on humans.

The CRISPR variant uses a virus that acts as a vector. Inside there is a small portion of gene that is added to the material already present. Formally speaking, the technique does not correct the mutation; rather, it overwrites it with more relevant genetic material. The genes that prevent the production of the ornithine transcarbamylase enzyme remain, but there are others that promote it.

Source: advances.sciencemag.org

A new genetic test could save hundreds of people from blindness. Researchers from the Berghofer Medical Research Institute and Flinders University have identified 107 genes linked to the risk of glaucoma. Starting with this discovery, they developed a way to identify patients who are most at risk of going blind.

To date, glaucoma is the leading cause of irreversible blindness in the world. To find out the causes, the study authors started from the genome of tens of thousands of people around the world, healthy and sick. Once genes were analyzed, they identified those related to the development of the disease. In this way, they were able to develop a genetic test to measure the risk of getting sick.

The test is still in the experimental phase: researchers are looking for 20,000 volunteers to carry out the research. If all goes well, the test will allow you to measure the risk of getting glaucoma. In addition, it will help to make an estimate of the possible severity of the disease, in order to identify the subjects who are most likely to lose their sight.

Will the test heal those who are already blind? To tell the truth, no: for the moment, there is no resolutive therapy for glaucoma. However, doctors can slow down or stop the progression of the disease, at least in most cases. Often the loss of vision is linked to a late diagnosis, which makes it impossible to intervene in time. The test in question could reduce such cases, giving a diagnosis to 50% of people with glaucoma who do not yet know they are.

Source: flinders.edu.au

In the past, geneticists had identified 17 genes underlying long QT syndrome. According to ClinGen experts, there may be far fewer. The researchers analyzed the evidence brought by previous studies, questioning the validity of some of these. From what emerges in the new study, only 3 of the 17 genes would be associated with the most common form of the disease.

It all began 20 years ago, when the New York Times reported the case of three boys who died for no apparent reason. Subsequent studies shed light on a semi-unknown heart disease, which killed around 4,000 young people in the United States in 2019 alone. According to the researchers, the deaths are said to be caused by mutations in the genes that regulate the electrical activity of the heart. All of a sudden, the muscle begins to beat irregularly or stops completely, killing the person.

Long QT syndrome often remains without a diagnosis, unless there have been other cases in the family. In such cases, experts recommend a genetic test for all the victim's closest relatives. This is where the study in question intervenes, which classifies and analyzes the 17 genes traditionally linked to the disease. According to the analyzes, the genes that explain most of the cases are only three: KCNQ1, KCNH2 and SCN5A.

Another 4 genes are linked to a form of the disease found only in infants. The other 10 genes, on the other hand, seem almost completely disconnected: according to the researchers, there is insufficient evidence of their actual role in the disease.

The discovery could improve both the understanding of the disease and its early diagnosis.

Source: eurekalert.org