[Analysis of ARSA gene variant in an infant with late infantile metachromatic leukodystrophy].

OBJECTIVE: To detect pathogenic variant of ARSA gene in an infant with late infantile metachromatic leukodystrophy (MLD). METHODS: The male proband had an onset of walking dysfunction and seizure at 28 months. Arylsulfatase A activity of his peripheral blood leucocytes was 26.9 nmol/mg.17h, and cranial MRI showed wild symmetrical demyelination. With genomic DNA extracted from his peripheral blood sample, all coding exons and splicing sites of the ARSA gene were subjected to Sanger sequencing. PubMed Protein BLAST system was employed to analyze cross-species conservation of the mutant amino acid. Ucsf chimera software was used to analyze the impact of candidate variants on the secondary structure of the protein product. Impact of potential variants was also analyzed with software including PolyPhen-2, Mutation Taster, SIFT and PROVEAN. Whole-exome sequencing was carried out to identify additional variants which may explain the patient's condition. RESULTS: The proband was found to harbor compound heterozygous variants of the ARSA gene [c.467G>A (p.Gly156Asp) and c.960G>A (p.Trp320*)], neither of which was reported previously. As predicted by Ucsf chimera software, the c.960G>A (p.Trp320*) variant may demolish important secondary structures including α-helix, ß-strand and coil of the ARSA protein, causing serious damage to its structure and loss of function. The c.467G>A (p.Gly156Asp) variant was predicted to be "probably damaging" by PolyPhen-2, Mutation Taster and SIFT software. CONCLUSION: The patient's condition may be attributed to the compound heterozygous c.467G>A (p.Gly156Asp) and c.960G>A (p.Trp320*) variants of the ARSA gene. Above results have facilitated genetic counseling and prenatal diagnosis for this family.

[Identification of a novel nonsense IQSEC2 variant in a child with X-linked intellectual disability].

OBJECTIVE: To explore the genetic basis for a child featuring X-linked intellectual disability. METHODS: The 1-year-and-6-month-old child presented with growth retardation, intellectual disability and bilateral alternating squint. With DNA extracted from the child and his parents' peripheral venous blood samples, whole exome sequencing was carried out to identify potential variants that can explain his condition. Suspected variants were validated by Sanger sequencing. The impact of variants was predicted by bioinformatic tools. RESULTS: The child was found to harbor a de novo nonsense c.3163C>T (p.Arg1055*) variant of the IQSEC2 gene. The variant, unreported previously, was predicted to be pathogenic based on MutationTaster, PROVEAN and SIFT. Analysis using a HomoloGene system suggested Arg1055 in IQSEC2 residues to be highly conserved evolutionarily, and that replacement of Arg1055 may cause destroy of the PH domain (AA 951-1085) and serious damage to the function of IQSEC2 protein. Analysis with UCSF chimera software suggested that the c.3163C>T (p.Arg1055*) variant can induce serious damages to the secondary structures of IQSEC2 protein, causing loss of its function. CONCLUSION: The patient's condition may be attributed to the de novo nonsense variant c.3163C>T (p.Arg1055*) of the IQSEC2 gene.

[MECP2 duplication syndrome: a clinical analysis of three cases and literature review].

MECP2 duplication syndrome (MDS) is a rare pediatric disease and mainly manifests as delayed motor development, language loss or delay, recurrent infection, severe intellectual disability, epilepsy, autistic symptoms, and early infantile hypotonia. In this article, the three children with this disease were all boys. Cases 1 and 2 had delayed motor development, and language loss or delay as initial manifestations, and case 3 had recurrent infection as initial manifestation. Physical examination showed hypotonia and negative pathological signs in each case. Case 1 had tonic-clonic seizures and electroencephalography showed focal seizures, for which he was given oxcarbazepine, levetiracetam, and clonazepam as the antiepileptic treatment to control seizures. Case 3 experienced one absence seizure and three head-nodding seizures with normal electroencephalographic findings during these seizures, and therefore, he was not given antiepileptic treatment. In each case, recurrent infection was improved with the increase in age, but there were no significant improvements in language or intelligence. Array-based comparative genomic hybridization (aCGH) showed MECP2 duplication in X chromosome in each case, and so they were diagnosed with MDS. MDS should be considered for children with delayed development complicated by recurrent infection and epileptic seizures, and early aCGH helps with the diagnosis of this disease.

Identification of novel CSNK2A1 variants and the genotype-phenotype relationship in patients with Okur-Chung neurodevelopmental syndrome: a case report and systematic literature review.

De novo germline variants of the casein kinase 2α subunit (CK2α) gene (CSNK2A1) have been reported in individuals with the congenital neuropsychiatric disorder Okur-Chung neurodevelopmental syndrome (OCNS). Here, we report on two unrelated children with OCNS and review the literature to explore the genotype-phenotype relationship in OCNS. Both children showed facial dysmorphism, growth retardation, and neuropsychiatric disorders. Using whole-exome sequencing, we identified two novel de novo CSNK2A1 variants: c.479A>G p.(H160R) and c.238C>T p.(R80C). A search of the literature identified 12 studies that provided information on 35 CSNK2A1 variants in various protein-coding regions of CK2α. By quantitatively analyzing data related to these CSNK2A1 variants and their corresponding phenotypes, we showed for the first time that mutations in protein-coding CK2α regions appear to influence the phenotypic spectrum of OCNS. Mutations altering the ATP/GTP-binding loop were more likely to cause the widest range of phenotypes. Therefore, any assessment of clinical spectra for this disorder should be extremely thorough. This study not only expands the mutational spectrum of OCNS, but also provides a comprehensive overview to improve our understanding of the genotype-phenotype relationship in OCNS.

EBV-associated myoid tumor with lipoblast-like cells in a patient with normal immunity.

EBV-associated myoid tumor (EBVMT) comprises a specific group of soft tissue tumors with divergent histologic appearances, which typically occur in immunocompromised patients. To the best of our knowledge, there have been no previous reported of EBVMT in patients with normal immunity. EBVMT with lipoblast-like cells (EBVMT-LIC) is an extremely rare variant of EBVMT. Here, a male patient with normal immunity and EBVMT-LIC is presented. Comprehensive EBV latency expression pattern and tumorigenesis molecular analyses are performed to detail the pathologic features of this disease. Our patient was a 14-year-old who suffered from Burkitt's lymphoma 6 years ago and got complete remission for 5 years. At his last visit, he presented with pain and weakness in arms and legs. Subsequent MRI revealed an extramedullary mass at the cervical areas. CT-guided resection was then performed and comprehensive histopathologic examination was conducted. We found a haemangiopericytoma-like pattern with EBER-positive lipoblasts exist in this neoplasm and these features were in accordance with the diagnosis of EBVMT-LIC. Also, the EBV type I latency pattern was observed and the activation of Akt/mTOR pathway and Bcl-2 overexpression were found to be involved in the tumorigenesis of EBVMT-LIC. In conclusion, the results of this study suggest that EBVMT can occur in patients with normal immunity. EBV could achieve a latency type I pattern and may promote the development of EBVMT by activation of Akt/mTOR pathway and Bcl-2 overexpression. The role of chronic latent EBV infection in the development of EBVMT may be more important than previously thought.

Atrial septal defect in a patient with congenital disorder of glycosylation type 1a: a case report.

BACKGROUND: Atrial septal defect often become more severe when encountered in genetic syndromes. Congenital disorder of glycosylation type 1a is an inherited metabolic disorder associated with mutations in PMM2 gene and can affect almost all organs. Cardiac abnormalities vary greatly in congenital disorder of glycosylation type 1a and congenital heart defects have already been reported, but there is little knowledge about the effect of this inherited disorder on an existing congenital heart defect. Herein we report for the first time on a baby with congenital disorder of glycosylation type 1a with atrial septal defect and make a comparison of changes in atrial septal defect by follow-ups to the age of 3. CASE PRESENTATION: Our patient was an 8-month-old Han Chinese boy. At the initial visit, he presented with recurrent lower respiratory infection, heart murmur, psychomotor retardation, inverted nipples, and cerebellar atrophy. Echocardiography revealed a 8 mm secundum atrial septal defect with left-to-right shunt (Qp/Qs ratio 1.6). Enzyme testing of phosphomannomutase 2 demonstrated decreased levels of phosphomannomutase 2 activities in fibroblasts. Whole exon sequencing showed he was heterozygous for a frameshift mutation (p.I153X) and a missense mutation (p.I132T) in PMM2 gene. The diagnosis of congenital disorder of glycosylation type 1a with atrial septal defect was issued. Now, he is 3-years old at the time of this writing, with the development of congenital disorder of glycosylation type 1a (cerebellar atrophy become more severe and the symptom of nystagmus emerged), the size of atrial septal defect increased to 10 mm and the Qp/Qs ratio increased to 1.9, which suggested exacerbation of the atrial septal defect. Congenital heart defect-associated gene sequencing is then performed and shows there are no pathogenic mutations, which suggested intrinsic cardiac factors are not the cause of exacerbation of the atrial septal defect in our patient and it is reasonable to assume congenital disorder of glycosylation type 1a can worsen the situation of the existing atrial septal defect. CONCLUSIONS: This report highlights the view that congenital disorders of glycosylation type 1a should be excluded when faced with congenital heart defect with cerebellar atrophy or neurodevelopmental delay, especially when the situation of congenital heart defect becomes more and more severe.

The protective effects of total phenols in magnolia officinalix rehd. et wils on gastrointestinal tract dysmotility is mainly based on its influence on interstitial cells of cajal.

Magnolia officinalix Rehd. et Wils is a kind of herb which is widely used for gastrointestinal tract mobility disorder in Asian countries. In this study, we investigated whether the total phenols of Magnolia officinalix Rehd. et Wils (TPM) treatment improves gastrointestinal tract dysmobility induced by intraperitoneal injection of atropine (5 mg/kg) in rats. Rats were randomly grouped into three units: TPM-pretreated/atropine-treated group, atropinetreated group and control group. TPM were administrated for 7 days. Gastric residual rate and intestinal transit were measured 20 min after atropine injected, and gastrointestinal hormones (including: gastrin (GAS), motilin (MTL), somatostatin (SS) and p substance (PS) levels in serum were also measured by ELISA kits. The number and distribution of interstitial cells of Cajal (ICCs) in stomach were detected by immunohistochemistry analysis, while c-kit and stem cell factor (SCF) expressions in stomach were also measured by western blotting. We found that TPM pretreatment significantly improved atropine-induced gastric residual rate increase, while had no significantly effects on intestinal transit; it also significantly normalized GAS, MTL and PS serum levels. Atropine-induced ICCs numbers decreased in both sinuses ventriculi and body of stomach, which is improved by TPM pretreatment. Western blotting results showed the expressions of c-kit and SCF were down-regulated after atropine injection, which can be reversed with TPM pretreatment. These results above indicates that TPM treatment can significantly protected atropine-induced gastric dysmoblility, which may owed to its regulation on c-kit/SCF signing pathway.