Researching their family histories, a deaf couple learns that some of their relatives back through several generations were also deaf. They plan to have a family and decide to discuss with a clinical geneticist the possibility that some or all of their children may be deaf. The geneticist informs them that without intervention they very likely will have a combination of deaf and normal hearing children, but that by using a combination of embryo testing and in vitro fertilization, it will be possible to select embryos with normal hearing for implantation. The couple opts for this method, and their first child has normal hearing.
Is it likely that these parents inherited their deafness as a recessive or dominant trait? What observations in the family histories would support either conclusion?
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Concepts of Genetics (12th Edition)
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