Aurora magazine

Scientists of four large US institution have joined forces to improve the diagnosis of rare genetic diseases. They are in fact combining the descriptions of the clinical features of patients with their genetic information.

In this way they started it unified analysis, seeking to more easily identify the diseases that involve more than one gene. The study is contributing to a better understanding of a large number of diseases, giving also its contribution to the prenatal screening techniques.

When looking for the cause of certain genetic diseases, we tend to locate in the mutation of a single gene. Yet according to Dr. Tamar Harel, one of the study authors, in many cases the genes involved are at least two. This creates a picture far more complex and difficult to decipher. To facilitate the diagnosis, the researchers decided to use a complete genome sequencing.

The scientists analyzed all the genes of 7,400 patients, all unrelated to each other. The purpose was to identify the genetic causes of their conditions, the result achieved in 2,076 patients, and about 28%. Of these 101, about 5%, were linked with a two or more genes of various diseases. A situation that, analyzed with traditional diagnostic tools, inevitably leads to inaccurate diagnosis because of the presence of different clinical features.

In some cases the symptoms of two different pathologies are partly overlapping. This leads perhaps to identify a single disease, tralasciandone another a little more hidden. In other cases, however, the presence of a large number of clinical features leads to allocate the case to a new unknown pathology. This makes the treatment less effective. In these situations it is therefore essential to intervene with a DNA test, as in the case in question.

The study allowed and is allowing to obtain a more complete perspective of how genes and physical traits relate. It is a key step in an era when medicine is becoming more personalized and precision. Thanks to it not only many patients have found an answer to their questions, but researchers have collected valuable data for diagnosis and prenatal screening tomorrow.

Source: news-medical.net

An Iranian test study that lack of exercise lowers male fertility. On the contrary, a moderate amount of cardio greatly increases the speed, the shape and the volume of the sperm. An interesting news for all those couples who are trying to have children, perhaps through assisted reproduction.

The study involved 261 sedentary men, divided into four groups according to the type of workout. The first were assigned 30 to 45 minutes of moderate journey at least three times a week; the latter has carried out high-intensity exercise such as sprinting three times a week; the third performed at high intensity exercise interspersed with walking; the members of the fourth had to do nothing. The first three groups showed a significant decrease in weight, body fat and waist circumference. Only men of the first group, however, have seen a significant improvement in sperm quality.

At the end of the first stage, the sperm of men who did moderate exercise had a larger volume of 8% compared to those who had not done anything. In addition, the mobility was increased by 12%, the morphology was 17% better, and there was 22% more sperm. After all four groups have stopped the exercises. The result of the stop was a return of sperm to the initial situation.

Researchers have not yet considered how moderate exercise has determined these improvements. The hypothesis is that causes a decrease in stress and inflammation, favorable for producing vibrant and healthy sperm. In any case, the moderate exercise could be a way to not only improve the quality of life in general, but also the chance of conceiving. A news of great importance for the many couples who are trying to have a child.

Source: huffingtonpost.com

Scientists of Prevention and Disease Control Centres have confirmed that, if contracted during the first months of pregnancy, by Zika virus infection increases the risk of microcephaly in the child. The article reported 476 cases of microcephaly in South America from January to November 2016, four times those recorded in the same period in 2015. Much of this is connected with two infections occurred in the first trimester of pregnancy, up early in the second.

The peak of microcephalic children in Colombia was in July 2016, with 94 cases. The event is linked to the peak of infections Zika came 24 weeks before the month concerned, then to January. The period corresponds more or less at the end of the first quarter and the beginning of the second of the women involved, which suggests that the infection has taken place in that period.

The authors, however, point out that it based the study on cases of microcephaly at birth. They have in fact counted children who demonstrated microcephaly months after birth. According to a Brazilian study, it would be a serious oversight, since there would be several cases of congenital infection Zika become manifest only in the postnatal period and therefore not detectable by prenatal testing.

The Centers for Prevention and Disease Control reported an increase in cases of Zika, even outside of the epicenter in Brazil. On the other hand, there was a decrease of waterborne infections by mosquitoes, at least in Miami. The credit would also be of reduced travel to the areas affected by the phenomenon, as recommended in August by the authorities.

Source: medscape.com

A molecular mechanism that regulates memory in bees could help combat neurodegenerative diseases. Researchers at the University of Queensland have found that molecular deficiency may trigger a series of physical changes, which affect the formation of new memories in insects. A phenomenon that some human diseases and thus helps to understand them better and to combat them.

Bees have a memory and a capacity for exceptional learning. They can count to four, they are oriented along routes learned by heart and mind maps. In addition they can interact with their peers, to act as teachers and pupils. They can show to their companions where are the best food sources and how to return to the hive. These processes resemble their human analogues, although they are so to say "summaries" in a smaller genome and simple. That is why the bees are a perfect model to study the evolution of neurodegenerative diseases.

The new memories are formed by molecular changes, which alter neural connections and their activities. Regulate some genes mediated process called epigenetic mechanism, DNA methylation. These regulate the expression of genes through DNA modifications or associations with protein, without changing the genes themselves. When the researchers tried to block the process, the bees have begun to show memory problems.

Scientists have taught to two groups of bees the connection between a particular odor and the presence of sugar. To the first group showed the connection a large number of times, the second only once. Then they took a sample of bees from both groups and they used on them an inhibitor, which has altered methylation of DNA. They then tried to teach a new connection, always with the previous method. From observations it showed that the treated bees had more difficulty learning new things.

Understand changes in the epigenome, how it manifests itself and how it affects brain function, can help to understand the evolution of a large number of diseases. Given the presence of a genetic predisposition, environmental factors may in fact determine when and how force manifest diseases such as dementia and Alzheimer's.

Source: eurekalert.org