Cristal Alicea‑Malavé and colleagues (led by Dr. Ruth Walker) studied the genetics of ‘VPS13A disease (chorea‑acanthocytosis) in Puerto Rico’, an ultra‑rare neurological condition caused by changes in the VPS13A gene.

This work was accepted as a Late-Breaking Abstract, and was presented by Cristal at the 6th Pan American Parkinson's Disease and Movement Disorders Congress, which took place between 13-15 February 2026 in Houston, Texas, USA.

Although VPS13A disease is found worldwide, the team noticed that more people than expected were being diagnosed in Puerto Rico, and in people of Puerto Rican ancestry in the mainland US. Their study confirmed this: they identified 17 patients from 14 families, which is unusually high for such a rare condition. A number of other patients have been diagnosed over the years using the chorein Western blot (currently performed in Germany by Dr. Kevin Peikert's Rostock team): Increased accessibility of genetic testing has led to this new work.

A key finding is that three specific genetic variants keep appearing in Puerto Rican patients.

The abstract states:

“Three recurring variants were identified […] At least one of the 3 alleles was present in each of the 12 patients.”

These recurring variants are likely founder mutations (genetic changes that appeared many generations ago and were passed down through families). The authors note:

“The 3 recurrent variants can be considered as ‘founder mutations’ and have likely been present in the population for many years.”

This helps explain why VPS13A disease may be several times more common in Puerto Rico than in other parts of the world.

This work is important because it can lead to:

• Earlier diagnosis
• Better genetic counselling for families
• More awareness among clinicians (e.g. for patients presenting with seizures or tics)
• Improved understanding of how the disease spreads in specific populations.