Genetic disorders may be classified into three major categories: (1) single gene disorders, (2) chromosome disorders, and (3) multifunctional disorders or the complex diseases.
Two examples of each categories, still following the orders above are: (1) Huntington's disease and cystic fibrosis, (2) Down's syndrome and Jacobsen symdrome, and (3) heart diseases and variations of cancers.
<span> one who treats afflictions of the nervous system is a(n)
d. neurologist.
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