Huntington's disease (MH) is an inherited disorder of degeneration characterized by a movement disorder progressively debilitating behavioral problems, sometimes very serious and affects the intellectual functions leading to dementia. Has a prevalence varying in different parts of the world with values in Europe about 5-10/100.000. In Italy, therefore is estimate that about 6,000 people and 18,000 sick those at risk of inheriting the disease. It was George Huntington in 1872, to describe for the first time the Huntington’s disease symptoms in his article "On Chorea."


Clinical features and genetic

The gene responsible for MH is located on chromosome 4. It contains information for the production of a protein called Huntington whose function is still unknown, although there is evidence that it is a protein essential to life and expressed in all cells. People with MH have alterations in the gene, and therefore their cells produce an abnormal form of this protein, which through an automatic gain functions toxic (gain-of-function) is not yet clarified, induces death of neurons in many brain areas.

In many cases, issues related to behavioral changes occur before Huntington’s disease symptoms occur of motor. The first signs of disease may be irritability, depression, mood changes along with a slight disturbance of motor coordination with mild and sporadic hyperkinesia-like shots. Slow movements (bradykinesia) or muscle contractures (dystonia) may characterize the onset of the disease by contributing to different variations depending on the case.

The age of onset is highly variable because the disease can manifest as a 2 to 90 years although it is generally the first symptoms appear on average between 30 and 50. The MH has a worsening trend that chorea and cognitive problems worsen as the disease progressed. Another common symptom is dysarthria, which is manifested as an alteration of the ability 'to articulate the language, often associated with difficulty swallowing.

Huntington in young people

In approximately 10% of cases, the MH strikes before the age of 20. Fortunately only rarely children or adolescents have this disease. Children most often inherit the disease from their father (MH is inherited with the same frequency from both parents). The symptoms of juvenile form of MH are sometimes different from the adult form, as in the case of the form defined Westphal. Initial symptoms usually involve slow, stiff, awkward gait, difficulty in speech and, sometimes, seizures occurring in 30-50% of cases. The course of the variant of youth may be more severe than that of adults. This group can 'be further divided into those with an outbreak of infantile or before 10 years and those with onset in adolescence 10 to 20 years of age'.


The MH is an autosomal-dominant and is transmitted from one generation to the next through the transmission from parent to child of a gene mutated (altered). Each child of an affected parent has one chance in two (50%) of having inherited the gene that causes MH, and is called "at risk". People who carry the gene develop MH unless they die from other causes before they have the first symptoms. Males and females have the same chance of inheriting the gene from affected parent. Those who have not inherited the gene do not develop the disease, and even their children.