Hello everyone,
In honor of Ehlers Danlos (EDS) and hypermobility spectrum disorder (HSD) Awareness Month (May), I’d like to talk about the different types of EDS. EDS is often talked about as a single condition, but in reality, it represents a group of connective tissue disorders with important differences in cause, clinical features, and medical risks.
At MKGenetix, we frequently work with individuals who have been told they “might have EDS” or who have hypermobility but are unsure how (or if) they fit into a specific subtype. In this post, we’ll break down the major types of EDS, how they differ, and why distinguishing between them can be clinically meaningful.
EDS Is Not One Condition
Ehlers-Danlos syndrome refers to a group of genetic conditions that affect connective tissue which is the structural framework that supports skin, joints, blood vessels, and internal organs. While all forms of EDS involve some degree of tissue fragility, the pattern of symptoms and associated risks can vary significantly by subtype.
Currently, there are 13 recognized subtypes of EDS. However, a few are more commonly encountered in clinical practice:
- Hypermobile EDS (hEDS)
- Classical EDS (cEDS)
- Vascular EDS (vEDS)
- Less common subtypes (e.g., kyphoscoliotic, arthrochalasia, dermatosparaxis)
Understanding where someone falls within this spectrum helps guide both management and expectations.
Hypermobile EDS (hEDS): The Most Common, Yet Least Genetically Defined
Hypermobile EDS is the most prevalent subtype and also the most complex diagnostically.
Key features often include:
- Generalized joint hypermobility
- Chronic joint pain and instability
- Frequent subluxations or dislocations
- As well as five (5) distinct other features such as
- Soft velvety skin
- Mildly hyperextensible skin
- Unexplained striae (stretch marks)
- Atrophic scarring in TWO areas (these are scars that appear to have divots or sunken areas
- Piezogenic papules (white bumps on the heels of the feet)
- TWO abdomnial hernias
- Prolapse of the uterus, pelvic floor, and/or rectum
- Dental crowding WITH a high palate
- Arachnodactyly (long fingers)
- Increased arm span-to-height ration
- Mitral valve prolaps
- Aortic root dilitation
- There are other symptoms which are not part of the criteria but commonly associated with hEDS including
- Fatigue
- Autonomic dysfunction (e.g. POTS)
- Gastrointestinal symptoms
- Mast cell activation syndrome (MCAS)
- Others
Unlike other forms of EDS, hEDS currently has no single confirmed genetic marker, and diagnosis is made clinically using established criteria.
Because there is no confirmatory genetic testing can still be valuable to help rule out other connective tissue disorders with known genetic causes such as those listed below.
Classical EDS (CEDS): Skin and Scarring as Key Clues
Classical EDS is typically caused by pathogenic variants in genes affecting type V collagen.
It is characterized by:
- Marked skin hyperextensibility
- Atrophic (thin, widened) scars
- Easy bruising
- Joint hypermobility (often present but variable)
Compared to hEDS, the skin findings are more prominent and distinctive, often providing an important diagnostic clue.
Genetic testing can confirm the diagnosis in most cases, which helps:
- Clarify prognosis
- Guide wound care and surgical planning
- Identify at-risk family members
Vascular EDS (vEDS): A Different Risk Profile
Vascular EDS is less common but medically significant due to its associated risks.
It is caused by variants in a gene affecting type III collagen and is associated with:
- Arterial aneurysm, dissection, or rupture
- Organ rupture (e.g., bowel, uterus)
- Thin, translucent skin
- Easy bruising
- Characteristic facial features in some individuals
Joint hypermobility may be present but is often less prominent than in hEDS.
The key distinction is vascular fragility, which requires:
- Ongoing cardiovascular surveillance
- Careful procedural planning
- Targeted lifestyle and activity considerations
Because of these risks, identifying vEDS is critical; not just for the individual, but for family members who may also be affected.
Rarer Subtypes: When the Presentation Doesn’t Fit the Typical Pattern
Several less common forms of EDS exist, each with unique features. For example:
- Kyphoscoliotic EDS: early-onset scoliosis, muscle hypotonia
- Arthrochalasia EDS: severe joint laxity and congenital hip dislocation
- Dermatosparaxis EDS: extreme skin fragility
These subtypes are rare but often have distinctive clinical presentations that prompt targeted genetic testing.
Why Subtype Distinction Matters
It can be tempting to think that labeling someone with “EDS” is sufficient, but in practice, the subtype can significantly impact care.
A more precise diagnosis can:
Guide medical monitoring
- Some subtypes require routine vascular imaging; others do not
Shape management strategies
- Physical therapy approaches differ depending on tissue fragility
- Surgical risks vary across subtypes
Clarify prognosis
- The long-term outlook differs between hypermobile, classical, and vascular forms
Inform family risk
- Many EDS types follow autosomal dominant inheritance
- Genetic confirmation allows for targeted testing of relatives
When to Consider Genetic Evaluation
A genetics evaluation may be particularly helpful if there are features that extend beyond generalized hypermobility, such as:
- Unusual or severe skin findings (e.g., atrophic scarring)
- History of arterial events, aneurysm, or organ rupture
- Early or severe varicose veins
- Distinct skeletal features (e.g., significant scoliosis, chest wall differences)
- A known family history of a specific EDS subtype
In these cases, genetic testing can help determine whether a defined subtype is present.
The Reality: Many People Fall in the Gray Zone
It’s important to acknowledge that not everyone will fit neatly into a defined category. Fortunately, new diagnostic criteria will be available at the end of this year which may help. However, there will still be some individuals that don’t fall into the clear buckets.
Many individuals have:
- Symptomatic hypermobility
- Chronic pain
- Multisystem involvement
…but do not meet full criteria for hEDS or another subtype.
These individuals may be described as having a hypermobility spectrum disorder (HSD) which is a diagnosis that is equally valid and still warrants thoughtful, multidisciplinary care. In addition, there are a lot of overlapping symptoms that are common in HSD (e.g. dysautonomia, gastrointestinal symptoms).
How Genetic Counseling Can Help
At MKGenetix, we work with individuals navigating uncertainty around EDS and related conditions.
Our role includes:
- Clarifying whether clinical features align with a specific subtype
- Determining whether genetic testing is appropriate
- Interpreting results in a practical, patient-centered way
- Helping coordinate care across specialties
- Providing education that connects symptoms into a cohesive framework
For many patients, the goal is not just a label, it is understanding.
Moving from Uncertainty to Clarity
EDS is a spectrum, not a single diagnosis and that distinction matters.
Whether someone has hEDS, a rarer genetic subtype, or falls within the hypermobility spectrum, identifying the right framework can:
- Reduce diagnostic confusion
- Improve care coordination
- Support safer, more tailored management
- Provide meaningful context for lifelong symptoms
If you’ve been told you “might have EDS” but don’t yet have clarity on what that means, you’re not alone and there are ways to approach that question more systematically.
How Can MKGenetix Help?
At MKGenetix, we provide virtual genetic counseling for individuals with suspected or diagnosed connective tissue disorders. We help you understand where your symptoms fit within the EDS spectrum and what steps—if any—are worth taking next.
If you’re trying to make sense of hypermobility, chronic pain, or a possible EDS diagnosis, we’re here to help you connect the dots in a way that is both clinically grounded and personally meaningful.
Knowledge, in this context, isn’t just information—it’s direction.
Warm regards,
Megan Trinkle-Knotts, MS, CGC
Certified Genetic Counselor
Founder, MKGenetix
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