The Ehlers-Danlos syndromes (EDS) are a group of heritable connective tissue 
disorders that share the common features of skin hyperextensibility, articular 
hypermobility, and tissue fragility. Considerable clinical and genetic 
heterogeneity exists, and more than nine separate forms have been recognized. 
Recent advances in the molecular analysis of EDS have identify defects 
responsible for EDS VI (homozygous and compound heterozygous mutations in the 
lysyl-hydroxylase gene), EDS VIIA and EDS VIIB (mutations in the type I 
collagene genes), EDS VIIC (deficiency of procollagen N-proteinase), EDS IX 
(mutations in the MNK gene), and EDS IV (mutations in the type III collagen 
gene). Of the various types of Ehlers-Danlos syndrome the most severe is type IV 
(EDS IV). Early studies showed that fibroblasts from EDS IV patients secreted 
lower than normal amounts of type III procollagen (Pope et al., 1975). Later, 
the disease was linked to COL3A1, the gene encoding this protein. More recently, 
with the publication of full length cDNA and partial characterisation of the 
gene structure, detailed analysis of mutations in EDS IV patients has become 
possible. Nineteen different mutations in the type III procollagen gene have 
been reported in different families with EDS IV. Recent results support the 
hypothesis that in EDS IV, dominant inheritance should be assumed, in sporadic 
cases also, unless proven otherwise. Very little is known about the genetics or 
biochemicals defects responsible for the others EDS subtypes, but with the 
applications of the tools of molecular biology, analysis of these defects if now 
within reach.