Aurora magazine

Preimplantation genetic tests are essential, but they are much earlier than a fetal DNA test. They can therefore lead to false positives and false negatives. To reduce this risk, an international team of researchers is working on a new technique.

Their goal is to increase the reliability of these tests and facilitate IVF. Current tests start with a small blastocyst biopsy, the very first phase of the embryo. The doctors take a sample of trophoblast, the tissue that gives rise to the placenta, and analyzes it. However, it happens that the cells of the trophoblast are healthy and those that will give rise to the embryo no, or vice versa. The phenomenon is called mosaicism and complicates genetic analysis.

The study authors developed a technique to analyze the cells contained in the culture fluid of the blastocyst. In this way it is easier to analyze different types of cells and it is more difficult to damage the blastocyst. It was tested by 52 blastocysts donated by patients who were undergoing fertility treatments.

They had all been analyzed using traditional techniques, allowing them to compare old and new results. The traditional technique has a false positive rate of 50%: out of 18 blastocysts considered abnormal, 9 were not. The new technique instead has a rate of 20%, still important but still much lower than the first. If perfected, it could facilitate pre-implantation analysis and therefore the selection of the best embryos for IVF.

Source: medicalxpress.com

Everyone knows the danger of gestational diabetes. According to a study led by Dr. Samantha Ehrlich, however, it is not necessary to arrive at real diabetes to have negative effects.

Too high glucose levels in pregnancy are indeed linked to a higher rate of obesity for the child. This while remaining below the threshold of the disease. In the United States, pregnant women monitor blood glucose levels between the 24th and 28th week.

The researchers analyzed these data and others, proceeds of over 40,000 pregnant women between 1995 and 2004. They crossed them with those of their children, followed up to 5-7 years of age. The analyzes showed a correlation between high levels of maternal blood glucose and filial obesity. Children of women with high glucose were 13% likely to become obese. In the case of gestational diabetes, the percentage even reached 52%.

The percentages include both women being same obese, and women completely normal-weight but with altered levels. It seems clear that there is a link between glucose and childhood obesity, which does not necessarily pass through the body mass index. According to the authors of the study, the prevention of childhood obesity could therefore also pass to the control of glucose levels.

Source: tennessee.edu

Type 2 diabetes depends on both environmental conditions and genetic predisposition, it is known. Yet the biological mechanisms underlying the disease are still unclear. For this reason, scientists from the University of Michigan have decided to expand the scope of traditional studies. Much of the research on diabetes is based on data collected from people of European origin.

This makes it harder to generalize the collected data, which does not take into account any variants present in other ethnic groups. For this study, instead, almost 46,000 people of all ethnic groups were involved, 21,000 suffering from type 2 diabetes and 25,000 healthy. In this way the researchers could rely on larger and more varied samples. Collect the samples, the researchers decided to reduce the radius of the analysis. They then concentrated on a particular portion of the genome, the one that codes for proteins.

This part of the genome is called an exome and represents only 2% of our entire genetic code. Research tends to underestimate it, but many recent studies are rediscovering it with surprising results. This is one of those. Thanks to this approach, the authors of the study found genetic variants related to the risk of diabetes ever observed, as they are rarer. A result already remarkable in itself, which however will require further studies and samples of even wider people.

Source: focus.it

Over the past 23 years, researchers have always linked depression to environmental and genetic factors. This has been since the first genetic factor linked to the disease was discovered. Nevertheless, a study published in the American Journal of Psychiatric could deny this correlation. According to the author, the correlation between the 18 genes identified to date and depression is based on statistically insignificant data.

It all starts with an analysis done in Colorado on a vast biodata bank. The analyzed sample includes about 620,000 individuals. The authors of the study combined a series of data:

• presence of genetic variants related to the disease;
• type of depression;
• environmental conditioning;
• child abuse;
• difficult socio-economic situations.

Apparently, no relevant link would have emerged between genes and major depression. According to the authors, therefore, the many cases reported in other studies would be false positives, probably caused by too small samples.

The genes would have nothing to do with depression. Almost. In reality, the authors of the study call for an in-depth study of possible genetic causes of the disease. However, they advise focusing primarily on the possible environmental causes, such as social conditions and lifestyle.

We are in fact far from having a clear and unambiguous idea of ​​what the actual causes of the major depression are. For Massimo Cozza, Director of the Department of Mental Health of the ASL Roma 2, the treatment of depression must take into account the complexity of the disease. Not only drugs, but also psychological, social and psychotherapy support. All taking into account the peculiarities of the individual.

Source: repubblica.it