Genetic predisposition of white matter infarction with protein S deficiency and R355C mutation
ABSTRACT The association between protein S deficiency (PSD) and ischemic stroke is controversial and warrants further investigation.
We conducted a genotype and MRI correlation study in a Chinese family in which hereditary PSD cosegregated with premature ischemic strokes. Six out of 11 family members inherited PSD type III in an autosomal dominant manner.
Among all PSD members, a novel missense mutation 1063C→T in exon 10 of protein S alpha (PROS1) was identified, which encoded a substitution of arginine to cysteine at position 355 (R355C) in the first globular domain of laminin A of protein S. Wild-type PROS1 sequences were retained in non-PSD members. MRI detected deep white matter infarctions predominantly distributed in the borderzone regions. The infarct topography was homogeneous in all adult mutant carriers. By contrast, cerebral infarction was absent in nonmutant carriers. Extensive investigation in the family did not reveal any confounding stroke risk. Haplotype analysis with high-density single nucleotide polymorphism markers revealed a 6.1-Mb minimally rearranged region (rs12494685 to rs1598240) in 3q11.2, lod = 3.0. Among the 7 annotated genes in this region, PROS1 is known to be associated with thrombotic disorders. MRI screening in an additional 10 PSD families without R355C showed no cerebral infarction.
PROS1 R355C mutation cosegregated with PSD type III and premature white matter infarctions in the index family. The findings substantiate an association between PSD and stroke. Study of the mechanism underlying this association may improve our understanding of premature cryptogenic white matter infarction.
SourceAvailable from: Sara-Joan Pinto-Sietsma[Show abstract] [Hide abstract]
ABSTRACT: Background: Cardiovascular disease (CVD) is characterized by slow progressive atherosclerosis and arterial thrombotic events, leading to occlusions. Whether either of these presentations is more likely in patients with a genetic predisposition for CVD is still unknown. We suggest that a genetic predisposition for CVD is related to recurrent events of the same nature. Methods: We retrospectively investigated 275 patients with premature CVD and divided them in two groups according to their first event: an arterial thrombotic event or stable atherosclerosis. We used a Cox proportional-hazards model to estimate the effect of a positive family history for CVD on recurrent events of the same nature. This was tested in the entire cohort and in patients with coronary artery disease only. Results: Patients with a first arterial thrombotic event and a positive family history had a threefold increased risk for a recurrent event of the same nature, compared to patients with a negative family history (hazard ratio 3.00, 95% confidence interval 1.32-6.81); p < 0.05). In contrast, a positive family history was not associated with an increased risk for a recurrent stable atherosclerosis (hazard ratio 0.98 (95% confidence interval 0.59-1.63). These findings were similar analysing the patients with coronary artery disease only. Additional adjustments for other risk factors did not change these associations. Conclusions: Patients with a first premature arterial thrombotic event and a positive family history for CVD have an increased risk for a second event of the same nature. This might be due to unknown hereditary mechanisms leading to recurrent acute events.European Journal of Cardiovascular Prevention and Rehabilitation 12/2012; 19(6):1465-1473. DOI:10.1177/1741826711422989 · 3.69 Impact Factor
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ABSTRACT: BACKGROUND AND PURPOSE: Occlusive radiation vasculopathy (ORV) predisposes head-and-neck cancer survivors to ischemic strokes. METHODS: We analyzed the digital subtraction angiography acquired in 96 patients who had first-ever transient ischemic attack or ischemic strokes attributed to ORV. Another age-matched 115 patients who had no radiotherapy but symptomatic high-grade (>70%) carotid stenoses were enrolled as referent subjects. Digital subtraction angiography was performed within 2 months from stroke onset and delineated carotid and vertebrobasilar circulations from aortic arch up to intracranial branches. Two reviewers blinded to group assignment recorded all vascular lesions, collateral status, and infarct pattern. RESULTS: ORV patients had less atherosclerotic risk factors at presentation. In referent patients, high-grade stenoses were mostly focal at the proximal internal carotid artery. In contrast, high-grade ORV lesions diffusely involved the common carotid artery and internal carotid artery and were more frequently bilateral (54% versus 22%), tandem (23% versus 10%), associated with complete occlusion in one or both carotid arteries (30% versus 9%), vertebral artery (VA) steno-occlusions (28% versus 16%), and external carotid artery stenosis (19% versus 5%) (all P<0.05). With comparable rates of vascular anomaly, ORV patients showed more established collateral circulations through leptomeningeal arteries, anterior communicating artery, posterior communicating artery, suboccipital/costocervical artery, and retrograde flow in ophthalmic artery. In terms of infarct topography, the frequencies of cortical or subcortical watershed infarcts were similar in both groups. CONCLUSIONS: ORV angiographic features and corresponding collaterals are distinct from atherosclerotic patterns at initial stroke presentation. Clinical decompensation, despite more extensive collateralization, may precipitate stroke in ORV.Stroke 01/2013; 44(2). DOI:10.1161/STROKEAHA.112.674036 · 6.02 Impact Factor