One of two major forms of a human condition called neurofibromatosis (NF 1)is inherited as a dominant, although it may be either mildly to very severely expressed. If a young child is the first in her family to be diagnosed, which of the following is the best explanation?

Question

Quizplus · Accepted Answer

Neurofibromatosis type 1 is inherited as a dominant trait, which means that only one copy of the gene is required to express the condition. If a young child is the first to be diagnosed, it is likely that one of the parents has a very mild expression of the gene, which may not have been recognized as NF1. Therefore, the child inherited the dominant gene from the affected parent and expressed the condition. The other answer choices are not likely in this scenario as the gene for NF1 does not skip generations and there is only one known allele of the gene.

One of Two Major Forms of a Human Condition Called