Is Huntington's Disease caused from a mutated gene?

How does the study of genetic disorders such as pku biologists understand normal alleles?

The similarities of organisms in which two areas numbered above provide the best evidence for common ancestry between organisms in both locations?

Nucleus has two lobes; contains granules of lysosomal enzymes; functions in attacking parasitic worms and plays complex roles in inflammatory diseases like allergies and asthma. what blood cells are described?