Final answer:
The statement that every generation will have the disease in the case of autosomal dominant inheritance is false. Both male and female offspring have the same likelihood of inheriting such diseases, and factors like reduced penetrance can affect whether the disorder is expressed in any given generation.
Step-by-step explanation:
The statement that every generation of a family will have the disease when it is an autosomal dominant disease is false. While autosomal dominant disorders do not discriminate by gender, meaning that male and female offspring have the same likelihood of inheriting the disease, not every generation will necessarily express the disease. This is due to the fact that while an individual needs only one copy of a dominant allele to display a dominant trait, factors such as reduced penetrance or a small family size can result in certain generations not expressing the disorder.
For example, disorders such as Marfan syndrome, Huntington's disease, and achondroplastic dwarfism are inherited in an autosomal dominant pattern, meaning they can be passed down from either parent to any child regardless of gender. A parent with a dominant allele for a disorder will have a 50% chance of passing the disorder to their offspring, but whether the allele actually manifests as the disorder can be influenced by other genetic factors.