By Crystal Lindell

We may be one step closer to discovering the specific gene mutations behind hypermobile Ehlers-Danlos syndrome (hEDS) — a connective tissue disorder that weakens collagen, muscles, ligaments and organs throughout the body, and makes joints highly flexible.

A research team at the Medical University of South Carolina has released the results of a genetic study of a family with high rates of hEDS. Five out of 11 family members met the clinical diagnostic criteria for hEDS and three were considered “probable.” 

Before we get too far into its conclusions though, it’s important to note that findings were released as a preprint in Research Square, which means they have not yet been peer-reviewed by a journal. As such, it’s in the early stages of release, and further scrutiny may result in changes to the conclusions.

That said, the researchers claim to have found what could be a variant linked to hEDS in the Kallikrein-15 gene, which is primarily expressed in the thyroid gland and other organs.

To check if this gene change actually causes hEDS, researchers used laboratory mice. After modifying the mice to have the same genetic variant, they found that the mice had similar connective tissue problems as seen in people with hEDS.

This supports the idea that the Kallikrein gene changes may play a role in causing hEDS.

But the research does not seem to show an all-encompassing hEDS gene. In a cohort of 197 hEDS patients, they found that less than a third (32.8%) had at least one KLK variant. Which means that over 60% of hEDS patients in the study did not have the variant.

As of now, hEDS is the only type of Ehlers-Danlos syndrome that does not have a known specific genetic marker, so finding one would be monumental. And even if this research doesn’t get us all the way there, it’s a huge step in the right direction.

Previous research has also associated hEDS to a genetic variant that causes a deficiency of folate, the natural form of Vitamin B9.

I should note here that I was diagnosed with hypermobile-EDS in 2018, so I have a lot of interest in the topic on a personal level. Since there is no genetic test currently available for hEDS, I was diagnosed via a physical assessment, along with my family’s medical history.

A lot of hEDS patients worry that if there ever is some sort of confirmed, definitive test like a genetic marker, they may not have the marker and would then “lose” their diagnosis.

Based on my personal experiences with medical professionals, I think that’s a legitimate fear. Doctors already seem unwilling to diagnose clear cases of hEDS for a variety of reasons, and this could just give them another excuse to continue doing that.

All I can really say is that if it happened to me, I would feel confident in knowing that my body is clearly not “normal” — so even if it’s not hEDS, there is something else impacting my health.

Some patients diagnosed with hEDS may actually be suffering from something else -- so a genetic test might help them to get the right diagnosis and treatment. I know that probably sounds naively optimistic to many patients. The more likely result is doctors telling patients nothing is wrong with them, and then sending them on their way to suffer.  

On the other hand, I think hEDS is so under-diagnosed, that having a definitive test for it would result in many, many more people finally getting an hEDS diagnosis.

Discovering the exact gene responsible for hEDS could also result in better treatments going forward. As of now, most doctors tell hEDS patients that there’s no cure, so all they can really do is treat the symptoms as they arise and avoid activities that could make their condition worse.  

This is purely wishful thinking, but perhaps in the future researchers will someday discover a way to actually strengthen our collagen and connective tissue, which could have countless benefits for patients suffering from the pain and other common hEDS symptoms.

Advancements like that still feel a long way off though, so until they happen, helping people get an hEDS diagnosis through a genetic test would be progress for millions of patients.