A study published in the journal Frontiers in Genetics exposes a new technique for predicting fragile X syndrome. This is a genetic test that identifies the presence of a specific type of genetic mutation. In this way he predicts the risk that a woman has a child with the disease.

Fragile X syndrome is linked to the expansion of CGG nuclei in the FMR1 gene. One patient with the syndrome shows more than 200 repetitions of CGG, compared with 30 averages. Sometimes the person has between 55 and 200 repetitions and shows milder disorders.

Women with this "premutation" have a high risk of having a child suffering from fragile X syndrome. The presence of repeats of the AGG nuclei reduces the risk, but remains present. A woman with 75 repetitions of CGG and two of AGG has 12% chance of transmitting the disease. The odds rise to 77% without AGG's double. Taking into account these two parameters, it is possible to evaluate the risk of hereditary transmission of the syndrome.

Identifying CGG repetitions is easy, but this does not apply to AGG repetitions. The researchers then developed a new genetic test that identifies AGGs in women with a premature FMR1.

The study involved about 51 women, including 26 carriers of a healthy gene and an intermediate gene, 24 carriers of a premutation. Only 1 woman showed both conditions. 30% of the second group (13 women) showed 60-80 repetitions of CGG. Of these, 3 had no repetition of AGG and were therefore at high risk. Other 2 had more than 85 repetitions of CGG and 1 had 95 repetitions and none of AGG. The latter had 100% chance of transmitting the syndrome.

Source: fragilexnewstoday.com

An international team from the Vrije Universiteit in Amsterdam has identified 939 new genes involved in the development of emotional intelligence and stability. The new genes are added to the 77 identified in previous studies.

For the first part of the research, the researchers involved a sample of about 270,000 subjects. In the second, on the other hand, they involved about 500,000 people. The second part focused on the genetic basis behind some mental disorders. On this occasion, scientists have identified a personality trait that increases the risk of incurring these problems.

To identify the genes in question, the researchers relied on genome-wide association studies. These collect the genetic variations of hundreds of thousands of genes by analyzing the presence and activities in thousands of subjects.

Scientists have identified high levels of expression in neurons in the hippocampus and striatum. These could be the genetic causes of the so-called fluid intelligence. The term fluid intelligence when an individual uses logical reasoning to find new solutions, no matter what knowledge you already have. It is in contrast to the crystallized intelligence, or the ability to make the best use of the knowledge that one has.

The study also identified a correlation between intelligence and Alzheimer's risk. Some genetic variants associated with intelligence appear to protect the brain from Alzheimer's and attention disorders. The researchers also focused on the genes on which emotional stability is based.

It seems that emotional stability resides in 599 genes. Some variants within these predispose emotional instability or neuroticism. Subjects who show variants are more likely than average to experience negative emotions. They are also more prone to depression and sometimes to schizophrenia.

Source: lescienze.it

A study by UT Southwestern identified the genetic mutation causing optic neuromyelitis. This is the most important genetic study so far conducted on the disease. Scientists have collected the DNA of over 1,200 patients. Thanks to the discovery, it will be possible to better understand the development of the disease and improve its treatments.

Optical neuromyelitis is a potentially fatal genetic disease. In those who suffer from it, the immune system attacks the cells of the optic nerves of the spinal cord. This causes blindness and paralysis. Some patients manage to recover thanks to treatments and rehabilitation. Many others receive a wrong diagnosis of multiple sclerosis and are at risk for permanent damage.

Genetic analyzes have unveiled a variation in a complementary component of a gene. The gene produces a protein that helps the antibodies to bind and damage everything that the antibodies attack. If the gene works well, the antibodies bind to harmful bacteria. In the case of neuromyelitis, the antibodies bind to parts of the nervous system which are then damaged.

Identifying the genetic variant, together with the clinical data, could facilitate the diagnosis. It will also be a way to immediately identify the best treatments for patients, based on the type of illness they suffer from. For some subjects the standard treatments are sufficient, for others not. For the moment we do not know the reason, but the DNA could give an answer.

Usually neuromyelitis optic appears along with other genetic diseases. It is rare that it occurs alone: ​​it affects about 0.3 US per 100,000. This makes it even more difficult to study it and understand its genetic mechanisms. The study in question aims to take a step forward, analyzing the whole genome and not just isolated portions like others.

Source: medicalxpress.com