Huntington's disease, which causes degeneration of neurons, runs in Maria's family. Huntington's is a heritable, autosomal dominant genetic disease. In an autosomal dominant disease, only one abnormal allele is required to cause the disease in offspring. However, it is possible that not all offspring will receive the abnormal allele from an affected heterozygous parent. Family members that have the disease include Maria's paternal grandmother and Maria's paternal uncles. Maria's paternal grandfather does not have the disease. Because symptoms of Huntington's disease do not appear until later in life, genetic testing is necessary to determine whether a younger individual possesses the allele for the disease. These tests determined that Maria's father does not carry the allele for Huntington's disease. Maria's maternal uncle suggested that Maria create a pedigree to track the disease in her family. Use the symbols provided to complete the pedigree. Each symbol may be used more than once.