What is the likely cause when a family has two children affected with osteogenesis imperfecta type II?

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Quizplus · Accepted Answer

Osteogenesis imperfecta type II is typically caused by new (de novo) mutations in the genes responsible for the condition, and it is usually lethal. When more than one child in a family is affected, and there is no family history of the condition, germline mosaicism in one of the parents is a likely cause. This means that some of the parent's germ cells (sperm or eggs) carry the mutation, even though the parent's somatic cells do not, leading to multiple affected offspring.

What Is the Likely Cause When a Family Has Two