Children with the common C1620A mutation met all of the criteria for the diagnosis of Hch with a severe phenotype that resembled achondroplasia and disproportionate short stature in early childhood.
Although we did not find a firm correlation between genotype and phenotype, in our study the N540K mutation was most often associated with disproportionate short stature, macrocephaly, and with radiological findings of unchanged/narrow interpedicular distance and fibula longer than tibia.