scholarly journals Association of De Novo RNF213 Variants With Childhood Onset Moyamoya Disease and Diffuse Occlusive Vasculopathy

Neurology ◽  
2021 ◽  
Vol 96 (13) ◽  
pp. e1783-e1791
Author(s):  
Amélie Pinard ◽  
Maximillian D.J. Fiander ◽  
Alana C. Cecchi ◽  
Andrea L. Rideout ◽  
Mohamed Azouz ◽  
...  

ObjectiveTo test the hypothesis that de novo genetic variants are responsible for moyamoya disease (MMD) in children with unaffected relatives, we performed exome sequencing of 28 affected children and their unaffected parents.MethodsExome sequencing was performed on 28 trios of affected patients with MMD and unaffected parents.ResultsWe identified 3 novel rare de novo RNF213 variants, 1 in the RING domain and 2 in a highly conserved region distal to the RING domain (4,114–4,120). These de novo cases of MMD present at a young age with aggressive MMD and uniquely have additional occlusive vascular lesions, including renal artery stenosis. Two previously reported cases had de novo variants in the same limited region and presented young with aggressive MMD, and 1 case had narrowing of the inferior abdominal aorta.ConclusionsThese results indicate a novel syndrome associated with RNF213 rare variants defined by de novo mutations disrupting highly conserved amino acids in the RING domain and a discrete region distal to the RING domain delimited by amino acids 4,114 to 4,120 leading to onset of severe MMD before 3 years of age and occlusion of other arteries, including the abdominal aorta, renal, iliac, and femoral arteries.

Author(s):  
Sana Amanat ◽  
Teresa Requena ◽  
Jose Antonio Lopez-Escamez

Exome sequencing has been commonly used in rare diseases by selecting multiplex families or singletons with an extreme phenotype (EP) to search for rare variants in coding regions. The EP strategy covers both extreme ends of a disease spectrum and it has been also used to investigate the contribution of rare variants to heritability in complex clinical traits. We have conducted a systematic review to find evidence supporting the use of EP strategies to search for rare variants in genetic studies of complex diseases, to highlight the contribution of rare variation to the genetic structure of multiallelic conditions. After performing the quality assessment of the retrieved records, we selected 19 genetic studies considering EP to demonstrate genetic association. All the studies successfully identified several rare variants, de novo mutations and many novel candidate genes were also identified by selecting an EP. There is enough evidence to support that the EP approach in patients with an early onset of the disease can contribute to the identification of rare variants in candidate genes or pathways involved in complex diseases. EP patients may contribute to a better understanding of the underlying genetic architecture of common heterogeneous disorders such as tinnitus or age-related hearing loss.


2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Yunfei Tang ◽  
Yamei Liu ◽  
Lei Tong ◽  
Shini Feng ◽  
Dongshu Du ◽  
...  

Autism spectrum disorder (ASD) is a complex neurological disease characterized by impaired social communication and interaction skills, rigid behavior, decreased interest, and repetitive activities. The disease has a high degree of genetic heterogeneity, and the genetic cause of ASD in many autistic individuals is currently unclear. In this study, we report a patient with ASD whose clinical features included social interaction disorder, communication disorder, and repetitive behavior. We examined the patient’s genetic variation using whole-exome sequencing technology and found new de novo mutations. After analysis and evaluation, ARRB2 was identified as a candidate gene. To study the potential contribution of the ARRB2 gene to the human brain development and function, we first evaluated the expression profile of this gene in different brain regions and developmental stages. Then, we used weighted gene coexpression network analysis to analyze the associations between ARRB2 and ASD risk genes. Additionally, the spatial conformation and stability of the ARRB2 wild type and mutant proteins were examined by simulations. Then, we further established a mouse model of ASD. The results showed abnormal ARRB2 expression in the mouse ASD model. Our study showed that ARRB2 may be a risk gene for ASD, but the contribution of de novo ARRB2 mutations to ASD is unclear. This information will provide references for the etiology of ASD and aid in the mechanism-based drug development and treatment.


2016 ◽  
Vol 96 (2) ◽  
pp. 179-185 ◽  
Author(s):  
K.D. Khandelwal ◽  
N. Ishorst ◽  
H. Zhou ◽  
K.U. Ludwig ◽  
H. Venselaar ◽  
...  

Common variants in interferon regulatory factor 6 ( IRF6) have been associated with nonsyndromic cleft lip with or without cleft palate (NSCL/P) as well as with tooth agenesis (TA). These variants contribute a small risk towards the 2 congenital conditions and explain only a small percentage of heritability. On the other hand, many IRF6 mutations are known to be a monogenic cause of disease for syndromic orofacial clefting (OFC). We hypothesize that IRF6 mutations in some rare instances could also cause nonsyndromic OFC. To find novel rare variants in IRF6 responsible for nonsyndromic OFC and TA, we performed targeted multiplex sequencing using molecular inversion probes (MIPs) in 1,072 OFC patients, 67 TA patients, and 706 controls. We identified 3 potentially pathogenic de novo mutations in OFC patients. In addition, 3 rare missense variants were identified, for which pathogenicity could not unequivocally be shown, as all variants were either inherited from an unaffected parent or the parental DNA was not available. Retrospective investigation of the patients with these variants revealed the presence of lip pits in one of the patients with a de novo mutation suggesting a Van der Woude syndrome (VWS) phenotype, whereas, in other patients, no lip pits were identified.


2021 ◽  
Author(s):  
Hanmin Guo ◽  
Lin Hou ◽  
Yu Shi ◽  
Sheng Chih Jin ◽  
Xue Zeng ◽  
...  

AbstractExome sequencing on tens of thousands of parent-proband trios has identified numerous deleterious de novo mutations (DNMs) and implicated risk genes for many disorders. Recent studies have suggested shared genes and pathways are enriched for DNMs across multiple disorders. However, existing analytic strategies only focus on genes that reach statistical significance for multiple disorders and require large trio samples in each study. As a result, these methods are not able to characterize the full landscape of genetic sharing due to polygenicity and incomplete penetrance. In this work, we introduce EncoreDNM, a novel statistical framework to quantify shared genetic effects between two disorders characterized by concordant enrichment of DNMs in the exome. EncoreDNM makes use of exome-wide, summary-level DNM data, including genes that do not reach statistical significance in single-disorder analysis, to evaluate the overall and annotation-partitioned genetic sharing between two disorders. Applying EncoreDNM to DNM data of nine disorders, we identified abundant pairwise enrichment correlations, especially in genes intolerant to pathogenic mutations and genes highly expressed in fetal tissues. These results suggest that EncoreDNM improves current analytic approaches and may have broad applications in DNM studies.


2021 ◽  
Vol 51 ◽  
pp. e120
Author(s):  
Karen Sánchez-Luquez ◽  
Simone Menezes Karam ◽  
Alicia Matijasevich ◽  
Iná da Silva dos Santos ◽  
Aluísio J D Barros ◽  
...  

2020 ◽  
Author(s):  
Vijaya Verma ◽  
Amit Mandora ◽  
Abhijeet Botre ◽  
James Premdoss Clement

Abstract Background : Exome sequencing is a prominent tool to identify novel and deleterious mutations which could be nonsense, frameshift, and canonical splice-site mutations in a specific gene. De novo mutations in SYNGAP1 , which codes for synaptic RAS-GTPase activating the protein, causes Intellectual disability (ID) and Autism Spectrum Disorder (ASD). SYNGAP1 related ASD/ID is one of the rare diseases that is detrimental to the normal neuronal developmental and disrupts the global development of a child. Results: We report a case of a child of 2-year old with global developmental delay, microcephaly subtle dysmorphism, absence seizures, disrupted sleep, delay in learning a language, and eating problems. Upon further validation, the child has a few traits of ASD. Here, based on focused exome sequencing, we report a de novo heterozygous mutation in SYNGAP1 exon 11 with c. 1861 C>T (p.arg612ter). Currently, the child is on atorvastatin and has shown considerable improvement in global behaviour and cognitive development. The long-term follow up of the child’s development would contribute to the already existing knowledge of the developmental trajectory in individuals with SYNGAP1 heterozygous mutation. Conclusion: In this report, we discuss the finding of a novel mutation in one of the genes, SYNGAP1 , implicated in ASD/ID. In addition, we discuss the current treatment prescribed to the patient and the progress of global developmental of the child.


Sign in / Sign up

Export Citation Format

Share Document