Regardless of some in vitro studies which indicated formation of polyQ inclusions that reduce levels of mhtt and the risk of neuronal death [10, 11], it was suggested that the aberrant protein huntingtin (mhtt) with an expansion of N-terminal polyglutamine tract causes preferentially degeneration of striatal neurons in patients with HD (e.g., [6]). The gene discussed is HTT; the disease is Huntington disease.