Some mutations in the SACS gene sequence may cause motor problems similar to those found in Charcot-Marie-Tooth disease (CMT). This is revealed by a Brazilian study published on Muscular Disorders.

To date, more than 20 genes have been identified that can be associated with different forms of CMT. Each form of the disease presents different neurological and systemic problems, superimposable with those of other neurodegenerative diseases. Nevertheless, they all share some clinical and biological traits that make it possible to link them all to the same disease.

Those suffering from CMT have a progressive degradation of the axonal section of the nerve cells. This hinders communication between nerve cells and that of peripheral nerves with the central nervous system. All this is manifested by symptoms of motor and sensory character.

In the study "Early-onset axonal Charcot-Marie-Tooth disease two to SACS mutation," a team of Brazilian researchers analyzed the cases of two unrelated men. Both suffered from diseases similar to CMT. At first the Charcot-Marie-Tooth had been diagnosed with them. Nevertheless, neither showed the typical nerve degeneration of the disease.

The researchers performed a complete sequencing of the two men's exome. They found that both patients showed genetic mutations concerning the SACS gene. These mutations had already been linked to the spastic ataxia of Charlevoix-Saguenay (ARSACS), which causes intellectual and physical deficits.

Neither patient showed symptoms typical of ARSACS, despite genetic mutation. In addition, the neuropathy they suffered was very similar to that of CMT, but had never been linked to the Charlevoix-Saguenay.

The finding suggests that mutations in the SACS gene could be associated with axonal sensory-motor neuropathies, but without other neurological symptoms.

Source: charcot-marie-toothnews.com

Marfan syndrome is a rare genetic disease that affects connective tissue. Only in Italy there are about 12,000-20,000 cases, of which 75% are hereditary. The cause of the disease is an alteration in the gene that codes for fibrillin-1, FBN1.

The disease affects in particular the heart and blood vessels, but also affects the ligaments and the skeletal system. Beyond some striking cases, Marfan's syndrome is difficult to diagnose without a genetic test. The most obvious clinical signs are:

• high height
• elongated limbs
• tapered fingers
• ectopia of the crystalline lens
• predisposition to dislocations
• alterations of the vertebral column
• lasso connective tissue

The laxity of the connective tissue has repercussions on various organs, such as heart and pomoni. In the case of the cardiovascular system, it mainly affects mitral valve and ascending aorta. For this reason, those suffering from Marfan syndrome are predisposed to aneurysm and aortic dissection.

In some cases, it is easy to confuse the symptoms with simple physical characteristics. Genetic screening is a great help in this regard and allows an accurate and fast diagnosis. Being a mainly hereditary disease in Marfan, the test is recommended for those who have family cases.

If Marfan syndrome is diagnosed, it is important that the patient is followed by a cardiologist. This will perform all the examinations necessary to identify any aortic dilatations and intervene before the break. If the dilatation is still in its infancy, it is possible to proceed with drug therapy. Otherwise surgery is necessary.

Source: osservatoriomalattierare.it

A team from the National Institutes of Health and University in Manchester has unveiled new details about the Chediak-Higashi syndrome (CHS). It is a rare genetic disease, of which about 500 cases are known all over the world and with devastating effects.

Chediak-Higashi sufferers show a large number of different symptoms. The subjects have a marked predisposition to bleeding and neurological problems. Furthermore, immune system malfunctions make them vulnerable to even the most common infections. In most cases, these people die from one of these infections.

The killer cells are immune cells with the task of eliminating aberrant cells, such as cancer cells, infected, malformed cells. They act by means of toxic enzymes that secrete into the cells to be eliminated. In subjects with CHS, killer cells fail to secrete these enzymes appropriately.

The team found that the immune cells of Chediak-Higashi sufferers have an abnormal cytoskeleton. Enzymes are too large to overcome the cell barrier, making killer cells useless. To solve the problem, the researchers used drugs that reduce the density of the cytoskeleton.

According to the first tests, reducing the density of the cell barrier restores the function of killer cells. This could have important repercussions on the patient's health and increase his chances of survival.

Source: manchester.ac.uk