Smooth Muscle Dysfunction Syndrome Research Articles

Elucidating the roles of SOD3 correlated genes and reactive oxygen species in rare human diseases using a bioinformatic-ontology approach.

Superoxide Dismutase 3 (SOD3) scavenges extracellular superoxide giving a hydrogen peroxide metabolite. Both Reactive Oxygen Species diffuse through aquaporins causing oxidative stress and biomolecular damage. SOD3 is differentially expressed in cancer and this research utilises Gene Expression Omnibus data series GSE2109 with 2,158 cancer samples. Genome-wide expression correlation analysis was conducted with SOD3 as the seed gene. Categorical SOD3 Pearson Correlation gene lists incrementing in correlation strength by 0.01 from ρ≥|0.34| to ρ≥|0.41| were extracted from the data. Positively and negatively SOD3 correlated genes were separated for each list and checked for significance against disease overlapping genes in the ClinVar and Orphanet databases via Enrichr. Disease causal genes were added to the relevant gene list and checked against Gene Ontology, Phenotype Ontology, and Elsevier Pathways via Enrichr before the significant ontologies containing causal and non-overlapping genes were reviewed with a literature search for possible disease and oxidative stress associations. 12 significant individually discriminated disorders were identified: Autosomal Dominant Cutis Laxa (p = 6.05x10-7), Renal Tubular Dysgenesis of Genetic Origin (p = 6.05x10-7), Lethal Arteriopathy Syndrome due to Fibulin-4 Deficiency (p = 6.54x10-9), EMILIN-1-related Connective Tissue Disease (p = 6.54x10-9), Holt-Oram Syndrome (p = 7.72x10-10), Multisystemic Smooth Muscle Dysfunction Syndrome (p = 9.95x10-15), Distal Hereditary Motor Neuropathy type 2 (p = 4.48x10-7), Congenital Glaucoma (p = 5.24x210-9), Megacystis-Microcolon-Intestinal Hypoperistalsis Syndrome (p = 3.77x10-16), Classical-like Ehlers-Danlos Syndrome type 1 (p = 3.77x10-16), Retinoblastoma (p = 1.9x10-8), and Lynch Syndrome (p = 5.04x10-9). 35 novel (21 unique) genes across 12 disorders were identified: ADNP, AOC3, CDC42EP2, CHTOP, CNN1, DES, FOXF1, FXR1, HLTF, KCNMB1, MTF2, MYH11, PLN, PNPLA2, REST, SGCA, SORBS1, SYNPO2, TAGLN, WAPL, and ZMYM4. These genes are proffered as potential biomarkers or therapeutic targets for the corresponding rare diseases discussed.

Whole-exome sequencing reveals the genetic causes and modifiers of moyamoya syndrome

Moyamoya vasculopathy secondary to various genetic disorders is classified as moyamoya syndrome (MMS). Recent studies indicate MMS occurs due to a combination of genetic modifiers and causative mutations for the primary genetic disorders. We performed whole-exome sequencing (WES) in 13 patients with various genetic disorders who developed MMS. WES successfully revealed the genetic diagnoses of neurofibromatosis type 1 (NF-1), Down syndrome, multisystemic smooth muscle dysfunction syndrome, Noonan syndrome, and alpha thalassemia. The previously reported modifier genes, RNF213 and MRVI1, were confirmed in the NF-1 and Down syndrome cases. Further analysis revealed rare hypomorphic variants in the causative genes of the primary disorders underlying MMS, such as Alagille syndrome and Rasopathies, conferred susceptibility to MMS. Genes involved in the development of pulmonary arterial hypertension (PAH), such as ABCC8 and BMPR2, were also identified as potential modifiers. The rare variants in the MMS and PAH genes were significantly enriched in the eight Japanese patients with MMS compared with the 104 Japanese individuals from the 1000 Genomes Project. Disease genes associated with the arterial occlusive conditions represented by those of Rasopathies and PAH may provide novel diagnostic markers and future therapeutic targets for MMS as well as moyamoya disease with an unknown cause.

Abstract WP223: Cerebral Visual Impairment in ACTA2 Patients Assessed by Virtual Reality Testing

Introduction: Heterozygous missense mutations disrupting arginine 179 (Arg179) in the ACTA2 gene which codes for the smooth muscle-specific isoform of α-actin, cause Multisystemic Smooth Muscle Dysfunction Syndrome (MSMDS). The clinical manifestations of this genetic condition include congenital mydriasis, patent ductus arteriosus, stroke, and/or aortic aneurysms or dissections among many others. White matter injury, impaired autoregulation, and neurovascular coupling (due to the cerebral vasculopathy affecting cerebral perfusion) are known factors that alter neural network performance and processing speed. The lack of a standardized ophthalmologic examination that detects cerebral visual impairment (CVI), precludes an early diagnosis and creates missed opportunities for intervention. There is a paucity of data regarding CVI in MSMDS patients, and through this novel work, we present data defining their visual processing deficits. Hypothesis: We hypothesize that: 1) individuals with MSMDS will exhibit more pronounced deficits in visual-spatial processing compared to the control group, and 2) their performance will deteriorate as the complexity of visual tasks increases. Methods: Using a virtual reality (VR) based visual search task system, we characterized the impairment of higher-order visual processing in MSMDS patients (n = 4) as compared to healthy controls (n = 13). The VR-based task required searching for targets on a screen among varying levels of visual complexity. Reaction time, gaze error, shifted ellipse area, success rate, and pursuit saccade ratio were statistically analyzed with unpaired group t-tests, with significance being defined as p < 0.05. Results: Compared to controls, MSMDS patients took longer to identify the correct target, were less accurate in finding the target, and exhibited greater impairment in performance with an increasing number of distractors. Both groups showed similar task compliance, measured using an off-screen count metric. Conclusion: This novel work demonstrates that MSMDS patients exhibit impaired higher-order visual processing. This highlights the need for clinical tools that can assess these difficulties with quantitative methods to guide therapies and improve functional outcomes.

Nuclear Smooth Muscle α-actin Participates in Vascular Smooth Muscle Cell Differentiation.

Missense variants throughout ACTA2, encoding smooth muscle α-actin (αSMA), predispose to adult-onset thoracic aortic disease, but variants disrupting arginine 179 (R179) lead to Smooth Muscle Dysfunction Syndrome (SMDS) characterized by diverse childhood-onset vascular diseases. Here we show that αSMA localizes to the nucleus in wildtype (WT) smooth muscle cells (SMCs), enriches in the nucleus with SMC differentiation, and associates with chromatin remodeling complexes and SMC contractile gene promotors. The ACTA2 p.R179 αSMA variant shows decreased nuclear localization. Primary SMCs from Acta2 SMC-R179C/+ mice are less differentiated than WT SMCs in vitro and in vivo and have global changes in chromatin accessibility. Induced pluripotent stem cells from patients with ACTA2 p.R179 variants fail to fully differentiate from neuroectodermal progenitor cells to SMCs, and single-cell transcriptomic analyses of an ACTA2 p.R179H patient's aortic tissue show increased SMC plasticity. Thus, nuclear αSMA participates in SMC differentiation, and loss of this nuclear activity occurs with ACTA2 p.R179 pathogenic variants.

Iris and Retinal Findings in Multisystemic Smooth Muscle Dysfunction Syndrome

Iris and Retinal Findings in Multisystemic Smooth Muscle Dysfunction Syndrome

A seed sequence variant in miR-145-5p causes multisystem smooth muscle dysfunction syndrome.

A seed sequence variant in miR-145-5p causes multisystem smooth muscle dysfunction syndrome.

Expanding ACTA2 genotypes with corresponding phenotypes overlapping with smooth muscle dysfunction syndrome.

Pathogenic variants in ACTA2, encoding smooth muscle α-actin, predispose to thoracic aortic aneurysms and dissections. ACTA2 variants altering arginine 179 predispose to a more severe, multisystemic disease termed smooth muscle dysfunction syndrome (SMDS; OMIM 613834). Vascular complications of SMDS include patent ductus arteriosus (PDA) or aortopulmonary window, early-onset thoracic aortic disease (TAD), moyamoya-like cerebrovascular disease, and primary pulmonary hypertension. Patients also have dysfunction of other smooth muscle-dependent systems, including congenital mydriasis, hypotonic bladder, and gut hypoperistalsis. Here,wedescribe five patients with novel heterozygous ACTA2 missense variants,p.Arg179Gly, p.Met46Arg, p.Thr204Ile, p.Arg39Cys, and p.Ile66Asn, who have clinical complications that align or overlap with SMDS. Patients with the ACTA2 p.Arg179Gly and p.Thr204Ile variants display classic features of SMDS. The patient with the ACTA2 p.Met46Arg variant exhibits exclusively vascular complications of SMDS, including early-onset TAD, PDA, and moyamoya-like cerebrovascular disease. Thepatient with the ACTA2 p.Ile66Asn variant has an unusual vascular complication, alarge fusiform internal carotid artery aneurysm. The patient with the ACTA2 p.Arg39Cys variant has pulmonary, gastrointestinal, and genitourinary complications of SMDSbut no vascular manifestations. Identifying pathogenic ACTA2 variants associated with features of SMDS is critical for aggressive surveillance and management of vascular and nonvascular complications and delineating the molecular pathogenesis of SMDS.

Triple bypass for multisystem smooth muscle dysfunction syndrome due to Arg179His ACTA2 mutation

Missense mutations in the smooth muscle-specific isoform of the alpha-actin (ACTA2) gene, which encodes smooth muscle actin, congenitally cause systemic smooth muscle dysfunction, leading to multiple systemic smooth muscle dysfunction syndrome. This disease is often diagnosed through the development of congenital mydriasis, patent ductus arteriosus, or thoracic aortic aneurysm at a young age. Some patients develop cerebrovascular lesions, also known as ACTA2 cerebral arteriopathy, which cause ischemic stroke and require surgical revascularization. However, an effective and safe treatment has not yet been established owing to the rarity of the disease. Furthermore, most reports of this disease involve children, with only a few reports on adults and few detailed reports on treatment outcomes published to date. We report a 46-year-old woman with ACTA2 cerebral arteriopathy caused by Arg179His, the most common mutation in this disease; she is the oldest patient reported with this disease to the best of our knowledge. The patient was diagnosed with multiple systemic smooth muscle dysfunction syndrome and ACTA2 cerebral arteriopathy after experiencing a stroke in the right cingulate gyrus. She underwent direct triple bypass with three anastomoses of the right superficial temporal artery to the middle and anterior cerebral arteries. She developed an ischemic stroke as a postoperative complication.The efficacy and safety of this procedure have not been clearly confirmed owing to the frailty of the donor superficial temporal artery and the poor development of collateral circulation; however, direct bypass should be considered a treatment option for patients experiencing progressive multiple strokes.

Cerebrovascular Disease Progression in Patients With ACTA2 Arg179 Pathogenic Variants.

To establish progression of imaging biomarkers of stroke, arterial steno-occlusive disease, and white matter injury in patients with smooth muscle dysfunction syndrome caused by mutations in the ACTA2 gene, we analyzed 113 cerebral MRI scans from a retrospective cohort of 27 patients with ACTA2 Arg179 pathogenic variants. Systematic quantifications of arterial ischemic strokes and white matter lesions were performed on baseline and follow-up scans using planimetric methods. Critical stenosis and arterial vessel diameters were quantified applying manual and semiautomated methods to cerebral magnetic resonance angiograms. We then assessed correlations between arterial abnormalities and parenchymal injury. We found characteristic patterns of acute white matter ischemic injury and progressive internal carotid artery stenosis during infancy. Longitudinal analysis of patients older than 1.2 years showed stable white matter hyperintensities but increased number of cystic-like lesions over time. Progressive narrowing of the terminal internal carotid artery occurred in 80% of patients and correlated with the number of critical stenoses in cerebral arteries and arterial ischemic infarctions. Arterial ischemic strokes occurred in same territories affected by critical stenosis. We found characteristic, early, and progressive cerebrovascular abnormalities in patients with ACTA2 Arg179 pathogenic variants. Our longitudinal data suggest that while steno-occlusive disease progresses over time and is associated with arterial ischemic infarctions and cystic-like white matter lesions, white matter hyperintensities can remain stable over long periods. The evaluated metrics will enable diagnosis in early infancy and be used to monitor disease progression, guide timing of stroke preventive interventions, and assess response to current and future therapies.

Molecular diagnostic in fetuses with isolated congenital anomalies of the kidney and urinary tract by whole-exome sequencing.

BackgroundIn prenatal care, accumulating evidences has demonstrated that whole‐exome sequencing (WES) expedites the genetic diagnosis of fetal structural anomalies. However, the clinical value of WES in the diagnosis of prenatal isolated congenital anomalies of the kidney and urinary tract (CAKUT) is unknown.MethodsForty‐one fetuses with unexplained isolated CAKUT, normal karyotype and negative chromosomal microarray analysis (CMA) results, underwent WES and were accordingly grouped as (a) Group 1: complex cases with bilateral renal abnormalities (N = 19); and (b) Group 2: cases with isolated unilateral fetal renal abnormalities (N = 22).ResultsThe detection rate of WES for pathogenic variants and incidental variants was 7.32% (3/41) and 2.4% (1/41), respectively. The three pathogenic variants were identified in the genes ACTA2 (multisystem smooth muscle dysfunction syndrome), PKHD1 (autosomal recessive form of polycystic kidney disease), and PKD1 (autosomal dominant polycystic kidney disease type 1). The incidental variants were detected in genes PPM1D (syndromic neurodevelopmental disorders). Furthermore, all above fetuses carrying pathogenic variants came from bilateral kidney anomalies. Thus, the detection rate was 0 for fetuses with unilateral fetal renal abnormalities and 15.7% (3/19) for bilateral renal abnormalities.ConclusionThis cohort shows that prenatal WES is a supplementary approach for the etiologic diagnosis of unexplained isolated CAKUT with negative CMA, especially for fetuses with bilateral renal abnormality.

Orphan Heritable Thoracic Aortic Diseases and Pregnancy. Modern Outlooks and Guidance

Pregnancy is a period of high risk for all patients with aortic pathology. Heritable thoracic aortic diseases (HTAD) refer to aortopathies with a high risk of formation and dissection of thoracic aortic aneurysm (TAA). HTAD are caused by a mutation of a certain gene. This paper reviews current perceptions of manifestations of rare hereditary diseases of the thoracic aorta during pregnancy and general recommendations for the medical care of these patients. To date, 16 genes (or loci of unidentified genes) are known to be associated with the development of thoracic aortic aneurysm, and since many families with a history of TAA (about 70%) have no pathogenic changes in any of these 16 genes, additional genes associated with HTAD have not yet been identified.
 In this paper, HTAD are considered which occur (or are identified) quite rare but provide a significant risk for patients, which is significantly increased during pregnancy (multisystemic smooth muscle dysfunction syndrome, Meester Lois syndrome, LOX and PRKG1 genes mutations, vascular Ehlers-Danlos syndrome, mutations in TGFB2, TGFBR1, TGFBR2, SMAD3 loci, Loeys-Dietz syndrome). The article analyzes the frequency of occurrence of the most threatening complication of HTAD – acute aortic dissection – in various syndromes, defines general recommendations for the examination of patients with HTAD, recommendations for conservative treatment of these patients. Recommendations for the patients (especially fertility women) concerning the preventive cardiac surgery are also summarized in the paper. These principles of pregravidary preparation and multidisciplinary medical support during pregnancy are the most effective prophylactic measures for major cardiac events and maternal death. Pregnancy heart team that has been working in Ukraine since 2013 does all its best to organize medical support for every pregnant woman with suspected HTAD. In this context, it is very important to collaborate with general practitioners and genetics to “catch” such patients before they become pregnant or in very early terms. Individualized plan of pregravidary preparation and medical care during pregnancy and delivery should be developed by a multidisciplinary team.

High-resolution iris and retinal imaging in multisystemic smooth muscle dysfunction syndrome due to a novel Asn117Lys substitution in ACTA2: a case report

BackgroundCongenital mydriasis and retinal arteriolar tortuosity are associated with the life-threatening multisystemic smooth muscle dysfunction syndrome (MSMDS) due to mutations in the gene, ACTA2, which encodes alpha-smooth muscle actin (α-SMA). Previous reports attributed MSMDS-related congenital mydriasis to the absence of iris sphincter muscle. Similarly, it has been hypothesized that abnormal proliferation of the vascular smooth muscle cells causes the marked tortuosity of retinal arterioles in MSMDS. In this report, high-resolution ocular imaging reveals unexpected findings that reject previous hypotheses.Case presentationThe proband is a 37-year-old female with a history of neonatal patent ductus arteriosus (PDA) ligation, left-sided choreiform movements at the age of 11 and a transient aphasia with right-sided weakness at the age of 30. Her older sister also had PDA ligation and congenital mydriasis but no neurological deficit up to age 41. Magnetic resonance angiogram demonstrated cerebrovascular lesions resembling but distinct from Moyamoya disease, characterised by internal carotid artery dilatation, terminal segment stenosis and absent basal collaterals. Their mother had poorly reactive pupils with asymptomatic cerebral arteriopathy resembling her daughters. All three had prominent retinal arteriolar tortuosity. The daughters were heterozygous and the mother was a somatic mosaic for a novel c.351C > G (p.Asn117Lys) transversion in ACTA2. Iris optical coherence tomography (OCT) showed a hyporeflective band anterior to the pigment epithelium indicating the presence of dysfunctional sphincter muscle. Adaptive optics retinal imaging showed no thickening of the arteriolar vessel wall whilst OCT angiography showed extreme corkscrew course of arterioles suggesting vessel elongation.ConclusionsIn addition to the known association between Met46, Arg179 and Arg258 substitutions and ACTA2-related arteriopathy, this case illustrates the possibility that Asn117 also plays an important role in α-SMA function within the cerebrovascular smooth muscle cell. MSMDS-related congenital mydriasis is due to reduced iris sphincter contractility rather than its absence. Retinal arteriolar tortuosity might be due to longitudinal proliferation of arteriolar smooth muscle cells. The described cerebrovascular and ocular signs are consistent with predicted effects of the novel Asn117Lys substitution in ACTA2.

MR Imaging Diagnosis of ACTA2

Smooth muscle alpha-2 actin (ACTA2) mutations are associated with diffuse smooth-muscle dysfunction syndrome and produce distinct imaging features. Clinical manifestations include intrathoracic large-vessel disease, nonreactive mydriasis, bladder hypotonia, and intestinal dysmotility. ACTA2 mutations are associated with childhood stroke due to diffuse cerebral arteriopathy distinct from moyamoya disease. Recognition of this syndrome has important clinical and prognostic implications. The purpose of this article is to review the unique imaging phenotypes associated with ACTA2 mutations, including vascular and nonvascular abnormalities.

Case report of multisystemic smooth muscle dysfunction syndrome in child

苏州大学附属儿童医院于2018年6月收治多系统平滑肌功能障碍综合征患儿1例，女，9个月18 d，其临床特点为反复咳嗽、喘息、气促。查体：双侧瞳孔散大、固定，直接及间接对光反射消失，右侧颜面部、颊黏膜、口腔舌部及上颚可见青紫色斑块，呼吸促，双肺可闻及湿啰音及哮鸣音，胸骨左缘可闻及收缩期Ⅱ/6级杂音。腹部B超显示胆囊结石，心脏超声提示卵圆孔未闭，主肺动脉内径增宽。头颅磁共振成像提示双侧脑室体部旁及半卵圆中心区异常信号。基因检测分析发现存在ACTA2基因c.536G>A(p.R179H)杂合突变。予吸氧、抗感染、平喘治疗2周后患儿病情逐步好转，出院后继续予氧疗、小剂量泼尼松口服治疗。多系统平滑肌功能障碍综合征是一种主要由ACTA2基因p.R179H变异引起的罕见遗传病，可引起全身性的平滑肌功能障碍，本例为国内第2例通过基因确诊的患者，提示临床医师对于存在瞳孔固定散大和/或动脉导管未闭的患儿应尽早行基因检测明确诊断。在其诊断及治疗过程中，临床医师应对脑血管、心血管及肺部并发症保持高度警惕。

Clinical history and management recommendations of the smooth muscle dysfunction syndrome due to ACTA2 arginine 179 alterations

PurposeSmooth muscle dysfunction syndrome (SMDS) due to heterozygous ACTA2 arginine 179 alterations is characterized by patent ductus arteriosus, vasculopathy (aneurysm and occlusive lesions), pulmonary arterial hypertension, and other complications in smooth muscle–dependent organs. We sought to define the clinical history of SMDS to develop recommendations for evaluation and management. MethodsMedical records of 33 patients with SMDS (median age 12 years) were abstracted and analyzed. ResultsAll patients had congenital mydriasis and related pupillary abnormalities at birth and presented in infancy with a patent ductus arteriosus or aortopulmonary window. Patients had cerebrovascular disease characterized by small vessel disease (hyperintense periventricular white matter lesions; 95%), intracranial artery stenosis (77%), ischemic strokes (27%), and seizures (18%). Twelve (36%) patients had thoracic aortic aneurysm repair or dissection at median age of 14 years and aortic disease was fully penetrant by the age of 25 years. Three (9%) patients had axillary artery aneurysms complicated by thromboembolic episodes. Nine patients died between the ages of 0.5 and 32 years due to aortic, pulmonary, or stroke complications, or unknown causes. ConclusionBased on these data, recommendations are provided for the surveillance and management of SMDS to help prevent early-onset life-threatening complications.

ACTA2 mutation and postpartum hemorrhage: a case report

BackgroundACTA2 encodes smooth muscle specific α-actin, a critical component or the contractile complex of vascular smooth muscle. Mutations in ACTA2 are the most common genetic cause of thoracic aortic aneurysm, and are also the cause of other disorders, including Moyamoya disease, coronary artery disease and stroke as well as Multisystemic Smooth Muscle Dysfunction Syndrome. We note that ACTA2 is also expressed in uterine smooth muscle, and this raises the possibility that women harboring ACTA2 mutations might exhibit uterine smooth muscle dysfunction.Case presentationWe present a young woman whose ACTA2 mutation was ascertained during pregnancy because of her father’s history of dissecting aneurysms. She was delivered at full term by cesarean section and subsequently had severe uterine hemorrhage due to uterine atony. Although her atony was successfully treated with uterotonic medications, she required blood transfusion.ConclusionsThis case raises the possibility that women with ACTA2 mutations may be at risk of uterine muscle dysfunction and hemorrhage. Obstetricians should be alerted to and prepared for this possibility.

Two patients with the heterozygous R189H mutation in ACTA2 and Complex congenital heart defects expands the cardiac phenotype of multisystemic smooth muscle dysfunction syndrome.

De novo heterozygous mutations changing R179 to histidine, leucine, or cysteine in the ACTA2 gene are associated with Multisystemic Smooth Muscle Dysfunction Syndrome (MSMDS). Characteristic hallmarks of this condition, caused only by these specific ACTA2 mutations, are congenital mydriasis (mid-dilated, non-reactive pupils), a large persistent ductus arteriosus (PDA), aortic aneurysms evolving during childhood, and cerebrovascular anomalies. We describe two patients, a 3-day-old newborn and a 26-year-old woman, with this unique mutation in association with a huge PDA and an aorto-pulmonary window. In addition, one showed a coarctation of the aortic arch and the other a complete interruption of the aortic arch type A; thereby expanding the spectrum of cardiac congenital heart defect of this syndrome. Each patient displayed a huge PDA and an extra-cardiovascular phenotype consistent with MSMDS. These observations exemplify that a functional alpha 2 smooth muscle actin is necessary for proper cardiovascular organ development, and demonstrate that a very exceptional congenital heart defect (aortopulmonary window) can be caused by a mutation in a gene encoding a contractile protein of vascular smooth muscle cells. © 2017 Wiley Periodicals, Inc.

Multisystemic Smooth Muscle Dysfunction Syndrome:An Unusual Cause for a Gigantic PDA with Bilateral Mydriasis

Objective: A patent arterial duct (PDA) is a common lesion usually treated by interventional measures. Rarely the PDA requires surgical intervention in babies > 2 kg body weight. Surgical intervention may also be required in premature babies and in those patients where the PDA exceeds the diameter of the aorta.

Congenital Fixed Dilated Pupils Due to ACTA2– Multisystemic Smooth Muscle Dysfunction Syndrome

Congenital fixed dilated pupils (congenital mydriasis) is characterized by hypoplasia or aplasia of the iris muscles, with absence of iris between the collarette and pupillary border, creating a scalloped pupillary margin. This condition has been reported in a multisystemic smooth muscle cell dysfunction syndrome, combined with congenital patent ductus arteriosus, cerebrovascular disease (Moya-moya-like), coronary artery disease, thoracic aorta aneurysm, and dysfunction of smooth muscle cells in organs throughout the body. All affected individuals carry a p.R179H heterozygous mutation in the ACTA2 gene. We add to the ophthalmologic involvement with 3 more patients. Congenital fixed dilated pupils is a rare condition and should alert ophthalmologists to the possibility of the coexistence of systemic life-threatening disorders.

Cerebral arteriopathy associated with Arg179His ACTA2 mutation

ACTA2 mutations have recently been shown to cause a multisystem smooth muscle dysfunction syndrome that may result in pediatric stroke. We report a case of ACTA2 mutation in a 3-year-old...