Molecular characteristics of arteries in patients with intracranial aneurysm: integration of WES and RNA-seq

Abstract

Genetic and vascular morphology research suggested intracranial aneurysm (IA) may not be a local artery disease. IA initiation may be correlated with the histological and molecular changes of arteries. We used whole-exome sequencing (WES) of blood and RNA sequencing (RNA-seq) of superficial temporal artery (STA) to explore the artery molecular characteristics of IA under the genetic background, and try to find the potential mechanism of the IA initiation. Fifty IA patients’ and 40 controls’ blood samples were enrolled in WES; 10 IA patients’ and 5 controls’ STA were included in RNA-seq. Bioinformatic analysis was performed. RT-qPCR was used for validation. We analyze the cell types of STA by the xCell algorithm, and conducted a correlation analysis between the endothelium and mutation genes. We identified 2118 genes via RNA-seq, and via WES 43 genes harboring 54 potential deleterious variants. Four genes (ALDH1L2, KCNJ12, SPNS2, TUBB8) had both variants and differential expressions. Xcell algorithms showed that the expression of mutation genes KCNJ12 and SPSN2 were strongly associated with decreasing endothelial cells on STA and higher IA risks. KCN12 and SPSN2 expressions have been validated by RT-qPCR. In total, we have described the artery molecular characteristics of IAs by RNA-seq and WES. A total of two gene mutations (KCNJ12 and SPSN2) were found potentially to facilitate IA initiation by decreasing EC expression in brain arteries.