Association Between SNAIL1 Gene Expression, SNAIL1 Genetic Variation, Vitamin D Receptor Gene Expression, and...

Asthma is a chronic inflammatory airway disease influenced by genetic and environmental factors. Low vitamin-D status has been implicated in asthma severity, while polymorphisms in the SNAIL1 gene, a transcription factor involved in epithelial-mesenchymal transition, may affect airway remodeling.

This exploratory study aimed to investigate the relationship between SNAIL1 genetic variants, SNAIL1 and vitamin-D receptor (VDR) gene expression, and vitamin-D status among Jordanian patients with asthma.

A case-control study was conducted involving 100 participants classified into four groups according to asthma status and vitamin-D status. Serum vitamin-D levels were measured, and SNAIL1 and VDR gene expression levels were analyzed using quantitative real-time PCR. Relative gene expression was calculated using the 2^-ΔΔCt method. SNAIL1 genetic variants were identified using PCR amplification followed by Sanger sequencing of the SNAIL1 coding exons.

Serum vitamin-D concentrations differed significantly among the study groups (p < 0.0001). SNAIL1 expression showed higher fold changes in asthmatic participants than in non-asthmatic participants, irrespective of vitamin D status; however, these differences did not reach statistical significance (p = 0.08-0.09). VDR expression demonstrated a decreasing trend in participants with low vitamin-D status, although most comparisons were not statistically significant. A novel missense variant in SNAIL1 (c.196C>T; p.Ala66Val) was identified in a single asthmatic participant with low vitamin-D status. This participant also exhibited higher SNAIL1 expression; however, the biological significance of this observation remains exploratory. In silico prediction tools classified this variant as benign, and its potential biological significance remains exploratory.

This study provides exploratory evidence suggesting potential relationships among SNAIL1 expression, VDR expression, vitamin D status, and asthma in a Jordanian population. The identified SNAIL1 variant represents a preliminary finding requiring further investigation. Larger studies with functional validation are needed to confirm these observations and provide a basis for future multidisciplinary research.