Final answer:
In this case, the trait is X-linked dominant. None of the sons have the trait, but all four daughters have it, indicating that the mother is likely affected. Genetic testing would be needed for confirmation.
Step-by-step explanation:
In studying an X-linked dominant trait, it is important to understand the inheritance pattern of X-linked traits. In this case, the trait is X-linked dominant, which means that only one copy of the mutant allele is needed for the trait to be expressed.
Since none of the sons have the trait, it is likely that they did not inherit the mutant allele from their mother. However, all four daughters have the trait, which suggests that they did inherit the mutant allele from their mother.
Based on this information, a likely conclusion about the patients is that the mother is affected with the X-linked dominant trait.
The sons did not inherit the trait because they received the Y chromosome from their father, while the daughters received the X chromosome with the mutant allele from their mother.
It is important to note that this conclusion is based on the assumption that the trait is X-linked dominant. It would be helpful to gather more information about the family and conduct genetic testing to confirm the inheritance pattern.