Molecular defects and cellular dysfunctions in restricted growth conditions

Restricted growth (RG) or dwarfism is a varied phenotype ascribable to many different causes, most of which are genetic. Conditions associated with disproportionate short stature (DSS) are usually caused by de novo dominant mutations in genes coding for proteins involved in cartilage/bone development. Rarer conditions, which may occur in inbred families, show an autosomal recessive inheritance. Causative mutations, consequent to cellular dysfunctions, genotype-to-phenotype correlations in RG conditions such as: Achondroplasia, Hypochondroplasia, Thanatophoric Dysplasia, Severe achondroplasia with delay in development and acanthosis nigricans, Pseudoachondroplasia, Multiple Epiphyseal Dysplasia, Diastrophic Dysplasia, Achondrogenesis, Osteogenesis Imperfecta, are discussed in this chapter.