Aurora magazine

Leber's congenital amaurosis is a genetic disease that causes progressive retinal degeneration. Over the years it causes severe low vision, which can even turn into blindness. It usually occurs around the first 6 months of life and is the most frequent cause of hereditary childhood blindness. About 3 children out of every 100,000 new born suffer from it. One of the typical symptoms of the disease is nystagmus, which is the uncontrolled movement of the eyes.

Together with the progressive loss of sight, it is the first distinctive element of Leber's congenital amaurosis. To confirm the diagnosis, the doctor analyzes the electrical activity of the retina and the genetic analysis. The disease is associated with 15-20 altered genes, although in 5-10% of cases it is linked only to RPE65 mutations. For the disease to manifest itself, the child must inherit two altered copies of the gene. Otherwise, the disease does not manifest itself and the child simply remains a healthy carrier. If there have been cases in the family, it is therefore advisable to take precautions with the appropriate genetic tests.

There are several forms of Leber congenital amaurosis, depending on the genes affected by the anomalies. For most forms, there is no cure and no definitive therapeutic protocol. The only exception is the form that affects the RPE65 gene, for which there is a gene therapy available since 2017. The doctor administers a virus that carries a correct version of the genus in the eye. The therapy has proved effective, especially if inoculated in the early stages of the disease.

Source: telethon.it

One of the things that makes Alzheimer's disease difficult to diagnose is the existence of symptomatic and not symptomatic versions. Despite having the same genetic variants and similar neurological conditions, some patients exhibit different levels of cognitive decline.

According to a study by the University of California, the phenomenon could be linked to the interaction of certain proteins. Family Alzheimer's has a strong genetic component, but the most common is sporadic Alzheimer's. Little is known of the latter. Its risk factors include age, gender and family history. However, social and biological factors that stimulate the accumulation of amyloid proteins also appear to contribute. By accumulating, the proteins form plaques that kill neurons and cause the typical symptoms of the disease.

The researchers studied 414 cases of diagnosed Alzheimer's, comparing it to a healthy control group. In doing so they went beyond genetic analysis and also analyzed the sum of mRNA molecules. From what has emerged, the presence or absence of interactions between proteins can modify how genes express themselves and how the disease evolves. Depending on the groups of genes involved, synaptic transmission and cellular metabolism also change. All critical aspects for sporadic Alzheimer's disease.

The discovery could facilitate early diagnosis of the disease, one of the biggest problems at the moment. A better understanding of how genes are linked and how proteins affect them, in fact, could help to develop tests to be used before the symptomatic phase.

Source: ucsd.edu

According to researchers at King's College London and the University of North Carolina, anorexia could have genetic bases. In fact, the study reveals some characteristics of metabolic diseases, all linked to 8 genetic variants.

The discovery is based on data collected from over 100 studies worldwide. In particular, the researchers combined the data collected by Anorexia Nervosa Genetics Initiative and Eating Disorders Working Group. In all, they examined 16,992 cases of anorexia and 55,525 people belonging to the control group, from 17 countries. A psychiatric and genetic picture emerged. From what has emerged, anorexia has traits of metabolic disorders of genetic origin. Until now, anomalies of this type were largely attributed to the lack of food. Yet, according to scholars, some of these are prior to the disease and are partly the cause.

They could even play an important role as psychiatric components. Many of these affect the way the body absorbs fats and also the propensity to exercise. This could explain why a good chunk of anorexic people is very active, despite the lack of nutrients. The problems in question intersect with other psychiatric disorders, such as OCD and depression. The authors of the study believe that a thorough analysis of the metabolic components could help to tackle the disease. If the findings were confirmed, in fact, all current treatments should be rethought.

Source: kcl.ac.uk

Familial dyskinesia with facial myokymia - or ADCY5-related dyskinesia - is a rare genetic disorder. It usually occurs in childhood, but there have also been cases of onset in late adolescence. The most characteristic symptoms are the uncontrolled paroxysmal movements of limbs and neck, which often also involve the face.

The severity of the disease varies based on the frequency and violence of the seizures. In the worst cases, it makes it impossible to walk and even talk, so much so that many subjects show delays in motor development. It seems that stress and anxiety contribute to worsening the severity of symptoms. On the other hand, the extent of dyskinesia tends to stabilize in adulthood.

The diagnosis of ADCY5-relata dyskinesia occurs through clinical observation and genetic tests, aimed at identifying ADCY5 gene abnormalities. The gene is expressed above all in the granular neuronal precursors of the cerebellum; the mutation could cause its overexpression.

The phenomenon could repress the hedgehog pathway of the embryonic neural tube, with all the consequences mentioned above. During the diagnosis, it is common for dyskinesia and epilepsy to be confused. However, the disease in question does not respond to epileptic drugs; usually it takes very little to exclude epilepsy with reasonable safety.

Uncontrolled facial movements can raise some doubts about multiple sclerosis and hereditary benign chorea. In these cases, the genetic test is used to identify the possible mutation of ADCY5. For the moment, there are no resolutive therapies against familial dyskinesia with facial myochemistry.

Source: orpha.net