Thanatophoric dysplasia: an autosomal dominant condition?

We present 13 cases of thanatophoric dysplasia collected in the Spanish Collaborative Study of Congenital Malformations from a total population of 517,970 births. The incidence (live and stillbirth) was 2.7 per 100,000 births. All cases were sporadic, and there was no evidence of parental consanguinity. Parental age was significantly higher as compared with control parents. These findings suggest the occurrence of autosomal dominant mutation, with an overall mutation rate of 1.34 X 10(-5) in our population, which is close to that observed in achondroplasia.