Which type of genetic transmission promotes the continued existence of genetic mutations in single genes?
A)Autosomal dominant
B)Autosomal recessive
C)Codominant
D)Sex-linked

Question

Quizplus · Accepted Answer

Recessive traits and disorders require two alleles (homozygosity) for expression. A person who has only one allele does not express the trait or disorder. Thus, the trait can "hide" for many generations but still be present in a population, although people may not be aware of its existence. When it is finally expressed because a heterozygous carrier of the trait or disorder has children with another heterozygous carrier of the same trait or disorder, it might be considered a "random" event, especially if the couple does not have another affected child. Dominant traits are more frequently expressed because one affected allele results in expression, and they are more obvious. Therefore, if the trait or disorder is expressed in early childhood in more than one family member, people consider the possibility that it is inherited. If the trait or disorder also is considered "undesirable," the affected individual may not be chosen as a mate for the purposes of having children. So, the key to the continued existence of recessive traits/disorders is the fact that problems are not obviously expressed in the heterozygous individual.

Which Type of Genetic Transmission Promotes the Continued Existence of Genetic