The inheritance pattern of dentinogenesis imperfecta is
**Core Concept**
Dentinogenesis imperfecta is a rare genetic disorder characterized by the formation of dentin that is discolored and brittle. It is caused by mutations in the DSPP gene, which encodes for the dentin sialophosphoprotein protein. This protein plays a crucial role in the mineralization and structure of dentin.
**Why the Correct Answer is Right**
The correct answer is associated with the autosomal dominant inheritance pattern. In dentinogenesis imperfecta, individuals with a mutation in the DSPP gene have a 50% chance of passing the mutated gene to each child. This means that if one parent has the condition, each child has a 50% chance of inheriting the mutated gene and expressing the condition. This is a classic example of autosomal dominant inheritance.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because autosomal recessive inheritance would require two copies of the mutated gene (one from each parent) for the condition to be expressed, which is not the case in dentinogenesis imperfecta.
**Option B:** This option is incorrect because X-linked inheritance would imply that the condition is more common in males, which is not the case in dentinogenesis imperfecta.
**Option C:** This option is incorrect because mitochondrial inheritance would imply that the condition is passed down from mother to child through the mitochondrial DNA, which is not the case in dentinogenesis imperfecta.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that dentinogenesis imperfecta is a rare genetic disorder, and its inheritance pattern is autosomal dominant. This means that if you suspect a patient has the condition, you should ask about their family history and perform a thorough examination to identify any affected relatives.
**Correct Answer: C. Autosomal dominant inheritance.**