This Publication Is Searchable The Merck Manual of Diagnosis and Therapy Section 21. Special Subjects Chapter 286.
Genetic disorders determined by a single gene are easiest to analyze and the most fully studied.
Many specific disorders have been described. A person need have only one abnormal allele of a gene for it to lead to an autosomal dominant disorder. A typical pedigree of an autosomal dominant trait is shown in Fig. An affected person and an unaffected person have, on average, an equal number of affected and unaffected children. Unaffected children of an affected parent have unaffected children and grandchildren.