Ehlers-Danlos syndrome-related genes and serum strontium, zinc, and lithium levels in generalized joint hypermobility: a case-control study.

Aim of the study: Generalized joint hypermobility (GJH) is a common feature of almost all Ehlers-Danlos syndrome (EDS) types; however, its genetic basis remains unclear. Therefore, it is crucial to distinguish the genetic basis of GJH from other connective tissue disorders, including the different subtypes of EDS. The aim of this study was to determine the blood EDS-related gene expressions and serum element levels in GJH and reveal their predictive characteristics and correlations with the Beighton score. Materials and Methods: A total of 39 women aged 18-23 years with GJH and 38 age- and sex-matched controls were included in the study. Inductively coupled plasma mass spectrometry was used to analyze the serum levels of zinc (Zn), strontium (Sr), and lithium (Li). The relative expression levels of the EDS-related genes were determined using quantitative real-time polymerase chain reaction (PCR). Results: Our results showed that women with GJH possessed significantly lower Li and higher Zn and Sr levels than the controls. In addition, the gene expressions of TNXB and SLC39A13 were significantly higher, whereas those of COL1A1, COL1A2, COL5A1, FKBP14, and DSE were lower in the GJH group. Pearson correlation analyses revealed a strong negative correlation between the Beighton score and B4GALT7, FKBP14, COL1A1, and Li. However, a significant positive correlation was noted between the Beighton score and SLC39A13, TNXB, Zn, Sr, and B3GALT6. Conclusion: Our findings provide valuable basal levels for conducting gene function analysis of joint hypermobility-related connective tissue disorders.