Ehlers-Danlos Syndrome

The Ehlers-Danlos syndromes (EDS) are a group of genetic connective tissue disorders characterized by joint hypermobility, skin hyper-extensibility, and tissue fragility. There is phenotypic and genetic variation among the 14 subtypes. However, the genetic basis of the hypermobile type of EDS (hEDS) remains elusive. hEDS is the most common type of EDS and involves generalized joint hypermobility, musculoskeletal manifestations, gastrointestinal symptoms, cardiovascular involvement and mild skin involvement such as abnormal scarring and skin hyper-extensibility. hEDS frequently occurs along with the presence of several comorbid conditions such as dysautonomia/POTS and mast cell activation syndrome (MCAS). It is estimated that the prevalence of hEDS to affect around 1 in 500 individuals, with varying degrees of severity and presentation.

Our lab is interested in the genetic causes of hEDS, the progression and underlying biology of the disease and ways to accurately diagnose and treat hEDS. We recently identified a strong candidate for hEDS and generated a genetically accurate mouse model to study the disease. This mouse model will allow us to understand the mechanisms involved in the development of the disease and act as a platform to test new diagnostics and treatment approaches.

We recognize that hEDS likely involves multiple genes. We are continuing to investigate additional genetic causes of hEDS, and how prevalent mutations in this gene are in the larger EDS population. Our group is also interested in the role of hormones in hEDS, mast cell activation syndrome, and gastrointestinal manifestations.

In the future, we hope to have a multidisciplinary connective tissue clinic for EDS clinical care and translational research at MUSC.

We have developed a patient registry and are still enrolling those with a clinical diagnosis of hEDS and their family members. To enroll in our patient registry to be a part of our genetic discoveries, you can fill out this survey. If you are eligible, a clinical research coordinator from the Norris Lab will contact you. Please do not fill out the link more than once. For any additional questions, email us at

If you are interested in learning about our hypermobile Ehlers-Danlos Intern Program, click here for more information.

Created with Biorender
Kohn, A., Chang, C. The Relationship Between Hypermobile Ehlers-Danlos Syndrome (hEDS), Postural Orthostatic Tachycardia Syndrome (POTS), and Mast Cell Activation Syndrome (MCAS). Clinic Rev Allerg Immunol 58, 273–297 (2020).