Assessing Intronic Variable Number Tandem Repeat (VNTR) Expansions of the HSF1 Gene in Essential Tremor Patients from Eastern China.

BACKGROUND

The association between intronic variable number tandem repeat (VNTR) expansions in intron 10 of the HSF1 gene and essential tremor (ET) has not yet been validated in larger, more diverse populations.

OBJECTIVES

This study aimed to investigate the association between HSF1 gene VNTR expansions and ET in the population of Eastern China.

METHODS

We screened 324 patients and 197 healthy controls (HCs) using fluorescence amplicon length analysis polymerase chain reaction (PCR) then precisely identified and analyzed repeat expansions at this locus by combining repeat-primed PCR with long-read whole-genome sequencing.

RESULTS

Despite identifying 18 patients (5.6%) carrying large HSF1 intronic VNTR expansions (>700 bp), our study found no significant difference in the overall distribution of repeat expansion lengths between the entire cohort of 324 ET patients and HCs, nor between familial and sporadic ET subgroups.

CONCLUSION

The amplification of this repetitive sequence in intron 10 of the HSF1 gene does not constitute a universal, major, or reliable genetic risk factor for ET. © 2026 International Parkinson and Movement Disorder Society.