Aurora magazine

A team of Chinese researchers used CRISPR to modify a human embryo. The article appeared in the journal Molecular Therapy. The authors describe the modalities used to eliminate a genetic defect from the embryo. According to reports, the technique used would be much more effective than those used in similar experiments. In addition, the researchers acted on an embryo obtained with IVF and potentially implantable in utero.

The first case of modified human embryo dates back to three years ago. Chinese researchers used a technique with a very low success rate. Out of 54 embryos, only 4 survived, all bearing a healthy version of the gene. Since then, researchers have created and used new variants of CRISPR.

The old genetic editing technique cut entire areas of DNA and replaced them with a healthy version. Instead, the new method exchanges DNA letters and corrects errors in a less invasive way. Chinese scientists used the latter to correct a mutation of Marfan syndrome. Those who suffer have an A instead of a G in the FBN1 gene: they have entered the correct letter.

The procedure was applied on 18 embryos. In 2 of these, the procedure changed other letters beyond those provided. Therefore, unforeseen genetic modifications have been created. According to the researchers, such errors are easy to identify and therefore there would be no risks.

In contrast to other times, the researchers modified embryos usable for IVF. If they wanted to, they could implant them in the womb of some women and let them develop. Before actually doing so, however, further studies will be necessary, so as to identify any negative consequences of the procedure.

Source: phys.org

An Australian research team has identified new genetic markers for glaucoma. The researchers involved over 134 thousand people from all over the world. Thanks to genetic analysis, they identified the anomalies that increase the risk of contracting the disease. Leading the international team was the Institute of Medical Research, University of Tasmania.

Scientists have identified 101 genetic markers, of which 85 unknown to date. The latter affect pressure in the eye, one of the reasons the disease develops. Thanks to the discovery, perhaps it will be possible to develop genetic tests for early diagnosis. In fact, today there are no ways to detect glaucoma in the very early stages.

Loss of peripheral vision is the first symptom of glaucoma, but appears only when the disease is already in an advanced stage. Dr. Alex Hewitt then led the present study, so as to make early diagnosis possible. According to the data collected, those who show genetic variants have 6 times the risk of developing the disease. There is more.

The treatments available today are aimed at reducing the pressure in the eye. The discovery of new genetic variants could offer alternatives, so as to develop new therapies. In addition, it would improve the diagnosis and offer the possibility to work on preventive treatments.

Source: ansa.it

Postmortem DNA analysis can help explain cases of sudden death by heart attack. However, expert professionals are needed to interpret the data, which is not always clear. For this purpose, the American College of Medical Genetics and Genomics (ACMG) has drafted a set of guidelines to follow. According to Dr. Steven White, these can help understand the causes of certain deaths and also to prevent the risk in the victim's relatives.

Genetic tests are usually thought of as a tool to prevent cardiovascular disease. Not always possible and it happens that some people die without an apparent reason. The so-called genomic autopsy is a way to diagnose post-mortem disease. Although it is useless for the person who has already left, it is very precious for siblings and children. In some cases, it can help prevent further deaths caused by the same genetic variant.

Death from sudden heart attack kills about 450,000 people a year in the United States. In most cases, deaths are caused by coronary or similar diseases. Nevertheless, among these there are 5,000 young people, of whom 40% died without an apparent reason. In these cases, traditional autopsies fail to give any answers. It is thought that the reasons for these deaths are hereditary cardiomyopathies, not diagnosed early.

Dr. Steven White examined 25 cases of sudden death left without explanation. Analyzing 99 genetic variants, he identified 27 anomalies common to 16 of the victims. These could be the cause of deaths.

Source: medicalxpress.com

A study by the University of Wisconsin-Madison has unveiled new details on how women's fertility works. Researchers have identified two genes working together to establish cellular communications in the ovaries. In guinea pigs, the system helps keep the oocytes healthy and guarantee their survival. The discovery could explain some cases of unexplained infertility and early menopause.

In the early menopause the ovaries stop producing estrogen, causing premature loss of the oocytes. This condition affects about 3% of women, in many cases without obvious symptoms. Previous studies by Dr. Jorgensen had revealed a possible cause. In guinea pigs without the IRX3 and IRX5 genes, follicles worked less well. This resulted in a smaller number of children, which made one think of fertility problems.

Going forward, the studies have revealed that the two genes are expressed in two different areas of the ovaries. Nevertheless, they are both essential for synchronizing oocytes and granular cells. The two types of cells expand the membranes by creating the junctions between them. In this way they communicate and regulate themselves in view of fertilization. Without the two genes, the process stops and the follicles remain destabilized.

Despite the findings made on guinea pigs, researchers are still not sure whether they are applicable to humans. The next step will be to check this point, but further studies will be needed.

Source: wisc.edu