Intracranial aneurysm's association with genetic variants, transcription abnormality, and methylation changes in ADAMTS genes

Abstract

Purpose. The development of intracranial aneurysm (IA) has been linked to genetic factors. The current study examines the potential role of genes encoding disintegrin and metalloproteinase using thrombospondin motifs (ADAMTS) in IA development. Material and Methods. High-throughput whole-genome and whole-exome sequenc- ing were used when screening for deleterious single-nucleotide variants (SNVs) in ADAMTS genes using samples from 20 Han Chinese patients: 19 with familial IA and one patient with sporadic IA. The variant frequencies in these subjects were compared to those in control individuals found in the Genome Aggregation Database. Transcriptome sequencing and methylation sequencing data were retrieved from the Gene Expression Omnibus (GEO) database to identify differentially expressed ADAMTS genes and their methylation sites. We predicted the network of interactions among proteins encoded by the overlapping set ofADAMTSgenes showing deleterious variants and both differential expression and abnormal methylation in IA. Possible candidate proteins linked to IA were validated using Western blot analysis. The associations between IA and SNVs rs11750568 in ADAMTS2, as well as rs2301612 and rs2285489 in ADAMTS13, were verified using the Sequenom MassArray system on a separate sample set of 595 Han Chinese patients with sporadic IA and 600 control individuals. Results. A total of 16 deleterious variants in 13 ADAMTS genes were identified in our patients, and seven of these genes overlapped with the genes found to be differentially expressed and differentially methylated in the GEO database. Protein- protein interaction analysis predicted that ADAMTSL1 was at the center of the seven genes. ADAMTSL1 protein was lower expressed in IA tissue than in the control cerebral artery. Frequencies of the IA-related SNVs rs11750568 in ADAMTS2 and rs2301612 and rs2285489 in ADAMTS13 were not significantly different between sporadic IA patients and controls. Conclusion. IA is associated with genetic variants, differential expression, and abnor- mal methylation in ADAMTS genes, ADAMTSL1 in particular.