The heterozygous individual for an autosomal dominant trait?

Question

Is a carrier or has the disorder?

Answer 1

The person will have the disorder, because the phenotype will be expressed if it's dominant.  

Answer 2

If the trait is inherited dominantly, then having one copy of the allele is enough to manifest the disorder. Examples of such disorders include Huntington's Corea, Marfan Syndrome, and Achondroplasia.