Since the 17th century, many humans have inherited, Huntington’s disease also known as HD, a genetic disorder that is passed down through families in which nerve cells in certain parts of the brain waste away, or degenerate. George Huntington was the first medical professional to make a full description on HD in his article “ On Chorea.” Huntington’s disease will cause the patient to have many brain activity malfunctions. When a patient inherits HD, at the age between 30 and 50 they will experience different brain activities, as the patient gets older. Early signs of the disease include slight, uncontrollable muscular movements, stumbling, minor memory loss, and a change in mood and behavior. Personality change will be the first sign in most cases; this can be noticed as much as 10 years prior to abnormal movements. Time passes and the symptoms will just get worse. Once 15 to 20 years passes after the first symptoms, death will usually take part by secondary illnesses such as, pneumonia or a more common one is difficulty swallowing, leads to choking. So, the time span of a person living with Huntington’s disease is only 15 to 20 years before death, but in those years they will lose their memory, ability to move around, and personality will change drastically. Everyone knows we have 46 chromosomes in our body, but the thing you don’t know, HD is caused by a genetic defect on chromosome 4. The defect causes a part of DNA, called a CAG repeat, to occur many more times than it is supposed to. Normally, this section of DNA is repeated 10 to 28 times. But in persons with Huntington's disease, it is repeated 36 to 120 times. HD results from genetically programmed degeneration of nerve cells, called neurons, in certain areas of the brain, which will cause the symptoms previously described. Specifically affects; the cells of the basal ganglia, coordination movement; neurons of the striatum; and the cortex, controls thought, perception, and memory. Parents give their children each 23 chromosomes. Also, they have two copies of each gene, but only give the child one gene. The gene that produces HD lies on chromosome 4, which is one of the 22 non-sex-linked, or "autosomal," pairs of chromosomes, placing men and women at equal