Which of the following is a risk factor for conceiving a child with a genetic disorder?

Having a family history of genetic disorders is a significant risk factor for conceiving a child with a genetic condition. This is because genetic disorders often follow specific inheritance patterns, such as autosomal dominant, autosomal recessive, or X-linked inheritance. If one or both parents carry genes associated with certain disorders, there is an increased likelihood that these genetic traits could be passed on to their offspring, leading to the expression of disorders in the child.

When assessing the other options, while age factors and specific parental genetic conditions can contribute to risk, they do not universally encompass the genetic predisposition that a known family history provides. For instance, the risk associated with being older than 35 is primarily related to chromosomal abnormalities like Down syndrome, which is more prevalent in older mothers. Similarly, both parents having a genetic disorder can suggest increased risk, but it varies significantly based on the specific condition and its inheritance pattern. The situation where both partners are younger than 35 is generally associated with lower risks for certain genetic disorders. Thus, known familial connections to genetic disorders present a clearer and more direct link to potential risks in offspring than the other factors mentioned.