Is achondroplasia hereditary?

Is achondroplasia hereditary?

• Most cases of achondroplasia are not inherited. Anyone can be affected by achondroplasia. Around 80% of individuals with achondroplasia have parents of normal height and are born with a new gene alteration (de novo mutation). It is rare that these parents will have another child with achondroplasia.
• Only one parent needs to pass down the gene for a child to be born with achondroplasia (autosomal dominant). There is a 50% chance of a person with achondroplasia and a partner who does not have achondroplasia having a child with the disorder.
• If both parents have achondroplasia, there is a 25% chance that the child will be born with homozygous achondroplasia, which leads to stillbirth or death shortly after birth.