Residents of the District of Columbia lack full democratic representation in the U. S. Senate or the U.S. House of Representatives. Representation in Congress is limited to a non-voting delegate to the House of Representatives and a shadow Senator.
Huntington's disease. Definition. Huntington's disease is an inherited disease that causes the progressive breakdown (degeneration) of nerve cells in the brain. Huntington's disease has a broad impact on a person's functional abilities and usually results in movement, thinking (cognitive) and psychiatric disorders.
Huntington's disease is caused by an inherited defect in a single gene. Huntington's disease is an autosomal dominant disorder, which means that a person needs only one copy of the defective gene to develop the disorder. With the exception of genes on the sex chromosomes, a person inherits two copies of every gene â one copy from each parent.