Two studies published in Nature Genetics have investigated the genetic basis of clinical insomnia. The disease affects about 1 in 10 people and undermines both physical and mental well-being. Researchers have suspected for years that there was a biological basis, but only recently have they identified some of the causes. From what has emerged, the genes involved would be the same ones that cause heart disease and psychiatric disorders.

The geneticist Danielle Posthuma, of Vrije University in Amsterdam, examined the DNA of over 1.3 million individuals. From this, he identified 202 areas of the genome linked to insomnia. The genes involved are 956, active mainly in brain regions commonly linked to insomnia. Simultaneously, geneticist Richa Saxena of Massachusetts General Hospital analyzed 450,000 genomes. This time the researchers identified 57 DNA regions, which include 236 genes. The results of the tests carried out confirmed what was found in the first study.

There seems to be an overlap between the genes discovered by Dr. Posthuma and those discovered by Dr. Saxena. Both studies highlight a large overlap between genes related to insomnia, genes linked to metabolic defects and genes linked to psychiatric diseases. People suffering from insomnia are often predisposed to depression, anxiety, schizophrenia, type 2 diabetes, coronary heart disease.

The problem therefore appears to be linked to neuropsychiatric disorders and mood regulation. Dr. Posthuma's group aims to increase the sample size. In addition, he is planning laboratory experiments to demonstrate the cause-effect relationship between insomnia and the cells involved. In this way it will be easier to elaborate new treatments, which complement the current cognitive-behavioral.

Source: lescienze.it

A study reveals a new genetic variation due to motor neuron disease. The discovery comes from a group of researchers from the Sheffield Institute for Translational Neuroscience (SITraN) and the NIHR Sheffield Biomedical Research Center (BRC).

The work could help find new ways to treat the disease, which currently affects around 5,000 people in the UK alone. Motor neuron disease is a set of neurodegenerative diseases that affect only motor neurons. People who suffer from it have a bad connection between brain and muscle, caused by the malfunction of this type of neuron. About 10% of cases are hereditary, while the remaining 90% is linked to sporadic genetic variations.

The study in question identified an unknown variation, which opens up a series of possible new therapeutic avenues. The researchers sequenced the DNA of two related patients, both affected by a familiar form of motor neuron disease. The analyzes revealed a mutation linked to an enzyme called GLT8D1.

Later, they searched for variation in another 103 patients. Of these, 5 presented the mutation. The discovery revealed a new genetic subtype of motor neuron disease. Thanks to it, it will be easier to understand how the disease develops and to seek new therapies.

Source: medicalxpress.com

A team identified a genetic abnormality linked to biliary atresia. This is the first discovery made in this sense and is thanks to an international team led by Dr. Saul J. Karpen. Thanks to this study, it will be possible to seek treatment for the disease. Biliary atresia is the leading cause of liver transplantation in children.

To date, the causes were completely unknown, which made it impossible to create a resolving therapy. Children suffering from the disease must undergo a difficult surgical procedure, which is not always sufficient. Sometimes the only solution that remains is liver transplantation, with all the associated difficulties.

The disease is very rare: large US hospitals see only a few cases per year. Furthermore, atresia is not hereditary in the usual sense of the word. According to some researchers, the gene is activated only in the presence of certain triggers, such as viruses or toxins. Despite the confusion and lack of resources, the team nevertheless collected data over the course of 15 years of study. Researchers have noted that 10% of atresia cases are related to heterotaxia, another genetic defect.

People who suffer from this condition have all their organs in an inverted position. When presented with biliary atresia, it is called BASM (biliary atresia associated with splenic malformation syndrome). The team then focused on 67 children with this form of atresia.

Thanks to total genome sequencing, mutations have emerged in the PKD1L1 gene. The gene encodes a protein produced in the bile duct cells. It is unlikely to be the cause of all cases of biliary atresia, but it is a fundamental first step to better understand this disease.

Source: whsc.emory.edu