Huntington Disease-Like 3 (HDL-3) disease is a dominant X-linked neurodegenerative disease that manifests in affected individuals around age 30. Shown below is a pedigree from a family with members showing the disease. All family members are well above age 30, except for IV-1 who is only 5 years old. Microsatellite locus r5984 is believed to be linked to the HDL-3. Researchers have typed each family member for r5984 using PCR; the gel with the PCR results is also shown.