The Ehlers-Danlos syndromes (EDS) are a group of 13 heritable connective tissue disorders caused by genetic changes that affect connective tissue. Connective tissue is found throughout the body and provides support, protection, and structure. Collagen is the primary component of connective tissue. There are different types of collagen, and the genetic changes that lead to EDS affect the production of specific types of collagen.

 

Some features are seen across all types of EDS, including joint hypermobility, skin hyperextensibility, and tissue fragility. Joint hypermobility means that a person’s joints have a greater range of motion than is expected or usual. Some people with joint hypermobility also have joint instability, which can lead to joint subluxations, dislocations, sprains, and other injuries. Skin hyperextensibility means that the skin can be stretched beyond the normal range. Tissue fragility means that the body’s organs and other structures are more vulnerable to damage.

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Each type of EDS has its own set of features with distinct diagnostic criteria. The current classification includes 13 types of Ehlers-Danlos syndrome. Each type has its own genetic causes, resulting in a unique set of features for each type of EDS. Hypermobile EDS (hEDS) is the most common type of EDS and is thought to affect at least 1 in 3,100-5,000 people. Classical EDS (cEDS) and vascular EDS (vEDS) are much rarer than hEDS. All other types of EDS are classified as ultra-rare, affecting less than 1 in 1 million people.

 

It is important to note that the true prevalence of EDS may be underestimated, and several types of EDS have only been reported in a few affected families. The genetic cause(s) of hEDS have not been identified yet.

In conclusion, EDS is a group of 13 heritable connective tissue disorders caused by genetic changes that affect connective tissue, leading to a unique set of features for each type of EDS, including joint hypermobility, skin hyperextensibility, and tissue fragility. It is a rare disorder, but the true prevalence is not known and may be underestimated. Further research is needed to better understand the causes and prevalence of EDS and improve the affected individuals' diagnosis and treatment.

Sources :
(Research organizations):  (Personal Research)
ehlers-danlos.com  Israa Al-Tayeh