AUTOSOMAL DOMINANT - Requires only one affected parent have the trait to pass it to offspring. The statistical risk of recurrence is 50%, regardless of the outcome of previous pregnancies; usually there is no sex predilection. In some cases there may be no family history for the condition and the mutation may be "fresh." In most cases, the affected individual risks transmitting the dominant mutation to one-half of his offspring. An example of this type of transmission is Huntington's disease.