Mutations in the COL5A1 Coding Sequence Are Not Common in Patients With Spontaneous Cervical Artery Dissections

Abstract

Background and Purpose-The dermal connective tissue of most patients with spontaneous cervical artery dissections (sCAD) contains abnormal collagen fibers. This suggests a predisposing connective tissue defect. The ultrastructural abnormalities in the skin of patients with sCAD have similarity with the morphological alterations in patients with Ehlers-Danlos syndrome type II, a dominant hereditary disorder that has been correlated in some patients to mutations within the genes encoding type V collagen. The aim of this study was to assess the alpha 1 chain of type V collagen (COL5A1) as a candidate gene for sCAD. Methods-We searched for mutations in the COL5A1 gene in cDNA from cultured fibroblasts of 19 patients with sCAD using single-strand conformational polymorphism analysis and nucleotide sequence analysis of polymerase chain reaction-amplified fragments of the whole COL5A1 coding sequence. Results-We detected 1 missense mutation leading to a predicted amino acid (192D/N) substitution within the N-terminal propeptide in 2 siblings. All other patients showed regular COL5A1 sequences with some silent polymorphisms. Conclusions-Mutations in the COL5A1 gene do not appear to be a major factor in the etiology of sCAD. (Stroke.1999;30:1887-1890.)Key Words: connective tissue disorders Ⅲ dissection Ⅲ genetics Ⅲ mutation S pontaneous cervical artery dissections (sCAD) are increasingly recognized as a cause of stroke among young and middle-aged patients. 1 A predisposing arteriopathy in these patients has been postulated. 2 A recent study by Brandt et al 3 substantiated the hypothesis of a predisposing defect in the extracellular matrix. These authors found ultrastructural abnormalities in skin biopsies of a majority of patients with sCAD and suggested an association with a connective tissue disorder. Major findings included numerous enlarged and irregular collagen fibrils and pronounced elastic fiber fragmentation. The abnormalities resembled the morphological alterations in patients with Ehlers-Danlos syndrome type II or III (EDS II/III). 4 Those changes were not observed in age-matched stroke patients with alternative etiologies of cerebral ischemic infarcts or in healthy control subjects. None of the patients with sCAD had other phenotypic manifestations of a known hereditary connective tissue disorder.Type V collagen belongs to the family of fibrillar collagens. [5][6][7] It is expressed at a low level in many tissues and plays an important role in type I fibrillogenesis by modulating and influencing fibril diameter. 8 -9 Mutations in COL5A1 and COL5A2 may lead to ultrastructural abnormalities similar to those observed in sCAD patients. 10 Furthermore, some patients with EDS I/II carry mutations in the COL5A1or the COL5A2 gene (for reference, see Michalickova et al 11 ). The ultrastructural similarities of dermal connective tissue aberrations of EDS II patients and sCAD patients prompted us to start this study and to analyze the full coding sequence of COL5A1 in patients with sCAD. Subjects and MethodsWe investig...

The Genetics of Cervical Artery Dissection

“…However, these studies have been markedly underpowered, mainly due to the low prevalence of CAD, which made it difficult to reach sufficient sample sizes; none *cDNA from cultured dermal fibroblasts. †These studies reported synonymous polymorphisms and genetic variants that were also found in healthy control subjects, considered as not being disease-causing mutations; 2 studies used single-stranded conformational polymorphism analysis (SSCP) to detect mutations 53,55 ; all other studies used direct sequencing.…”

A Systematic Review of the Risk Factors for Cervical Artery Dissection

“…[32][33][34]39,47,48 None of the identified mutations, however, was suggested to play a major role in the cause of CAD.…”

MMP-9 Polymorphisms Are Not Associated With Spontaneous Cervical Artery Dissection

“…2 Thus far, the tested candidate genes for mutations in ECM molecules, for example, collagen V, have been negative. 5 An alternative pathophysiological mechanism could be vessel wall alteration by MMPs. Recently, naturally occurring sequence variations have been detected in the promotor region of MMP genes.…”

“…5 For restriction fragment length polymorphism analysis, the 435-bp polymerase chain reaction product containing the C-1562T SNP was digested with NspI restriction enzyme and run on a 2% agarose gel stained with ethidium bromide (Figure 1). Sequencing was performed in only a few individuals to confirm the nature of each band seen on the gels.…”