Haiku. Haiku is an ancient form of Japanese poetry that counts sounds, as opposed to words. Its traditional form is three lines, with five sounds in the first line, seven in the second line, and five in the third line.
Single gene disorders can be: Dominant. An abnormality occurs when only one of the genes from one parent is abnormal. If the parent has the disorder, the baby has a 50 percent chance of inheriting it. Examples include the following: Achondroplasia.
HD is called an autosomal dominant disorder because only one copy of the defective gene, inherited from one parent, is necessary to produce the disease. The genetic defect responsible for HD is a small sequence of DNA on chromosome 4 in which several base pairs are repeated many, many times.