Clinical and molecular genetic characterization of familial MECP2 duplication syndrome in a Chinese family.

BACKGROUND: Chromosomal duplication at the Xq28 region including the MECP2 gene, share consistent clinical phenotypes and a distinct facial phenotype known as MECP2 duplication syndrome. The typical clinical features include infantile hypotonia , mild dysmorphic features, a broad range of neurodevelopmental disorders, recurrent infections, and progressive spasticity. METHODS: This Chinese MECP2 duplication syndrome family includes six patients (five males and one female), and four asymptomatic female carriers. Two kinds of chips including 4x180K CNV + SNP chip and custom 8x60K CNV chip were used to detect MECP2 duplication, and then fluorescent in situ hybridization (FISH) analysis was performed to identify the exact copy number of MECP2. X-chromosome inactivation (XCI) analysis on AR gene was detected for all female family members, and the m icrosatellite analysis on MECP2 was used to validate the recombination event on MECP2 region. RESULTS: The affected male subjects presented with a broad range of neurodevelopmental symptoms (severe intellectual disability, developmental delay, seizure, language deficit, and autism spectrum disorder) as well as facial dysmorphism and other symptoms which were consistent with that of Western patients previous reported. Seizure is reported in Chinese patients for the first time. In addition, we validated three recombination events for the MECP2-duplication allele during maternal transmission due to X homologous recombination. CONCLUSIONS: We provided the largest known Chinese pedigree with MECP2 duplication syndrome. The detailed clinical description and molecular genetic characterization in all affected family members further delineate the typical phenotype of this genomic disorder in Chinese population.

Streptococcal infection and immune response in children with Tourette's syndrome.

BACKGROUND: Streptococcal infection and basal ganglia inflammation are hypothesized to be involved in Tourette's syndrome (TS). There is a need for effective therapies for managing TS. We studied streptococcal infection and immunity in TS following immunomodulator (pidotimod) therapy. METHODS: Blood samples from 58 patients with TS and 128 age-matched healthy controls enabled measurement of antistreptolysin O (ASO), T cells, natural killer (NK) cells, interleukin-6 (IL-6) and interleukin-8 (IL-8), and tumor necrosis factor-α (TNF-α). Forty-four patients with abnormal T cell numbers were divided into two groups and treated with pidotimod granules (pidotimod group, n = 20) or pidotimod plus dopaminergic receptor antagonists (combination group, n = 24). Yale Global Tic Severity Scale (YGTSS) scores and immunologic indices were assessed after treatment. RESULTS: An ASO >1:200 was found in 22.4% of children with TS, 7.5% of controls, and 38.9% of children with both TS and attention deficit hyperactivity disorder (ADHD) compared to 15.0% of children with TS alone (P < 0.05). Children with TS showed decreased CD3(+) and CD4(+) T cells, CD4(+)/CD8(+) ratio, IL-6 and IL-8, increased NKC and TNF-α (P < 0.05) as compared to controls. ASO-positive children with TS had lower CD4(+) T cells as compared to ASO-negative children with TS, and lower IL-6 and IL-8 levels as compared to controls (P < 0.05). After 8 weeks of pidotimod treatment, IL-8 was increased compared to either tiapride hydrochloride or haloperidol and pidotimod (P < 0.05). CONCLUSIONS: Streptococcal infection in TS patients is associated with immune and cytokine dysfunction, which can be potentially managed with immunomodulator therapy.

Involvement of tryptophan hydroxylase 2 gene polymorphisms in susceptibility to tic disorder in Chinese Han population.

BACKGROUND: Tryptophan hydroxylase-2 (TPH2) is a potential candidate gene for screening tic disorder (TD). METHODS: A case-control study was performed to examine the association between the TPH2 gene and TD. The Sequenom® Mass ARRAY iPLEX GOLD System was used to genotype two single nucleotide polymorphisms (SNPs) of the TPH2 gene in 149 TD children and in 125 normal controls. RESULTS: For rs4565946, individuals with the TT genotype showed a significantly higher risk of TD than those with TC plus CC genotypes [odds ratio (OR) =3.077, 95% confidence interval (CI): 1.273-7.437; P = 0.009], as did male TD children with the TT genotype (OR = 3.228, 95% CI: 1.153-9.040; P = 0.020). The G allele of rs4570625 was significantly more frequent in TD children with higher levels of tic symptoms (Yale Global Tic Severity Scale, YGTSS) than those in controls among the male children (OR = 1.684, 95%: 1.097-2.583; P = 0.017]. TD children with severe tic symptoms had significantly higher frequencies of rs4546946 TT genotype than did normal controls in boys (OR = 3.292, 95% CI: 1.139-9.513; P = 0.022). We also found that genotype distributions of both SNPs were different between the Asian and European populations. CONCLUSIONS: Our results indicated that the TT genotype of rs4565946 is a potential genetic risk factor for TD, and the allele G of rs4570625 might be associated with the severity of tic symptoms in boys. These polymorphisms might be susceptibility loci for TD in the Chinese Han population. Because of the confounding of co-existing attention deficit hyperactivity disorder (ADHD),these findings need to be confirmed by studies in much larger samples.

[Point mutation analysis of SMN1 gene in patients with spinal muscular atrophy].

OBJECTIVE: To identify the point mutations in survival motor neuron gene 1 SMN1 gene and confirm the existence of compound heterozygous mutations in Chinese patients with spinal muscular atrophy (SMA). METHODS: Three unrelated patients were diagnosed and clinically typed according to the criteria of proximal SMA established by the International SMA Consortium. Multiplex ligation-dependent probe amplification (MLPA) analysis was carried out to measure the copy numbers of SMN1, SMN2 and neuronal apoptosis inhibitory protein gene (NAIP)in the patients. The point mutation analysis of SMN1 gene was performed by reversed transcript-polymerase chain reaction (RT-PCR) and cloning sequencing. The MLPA assay and point mutation analysis were also performed in the family members to confirm the transmission of the mutations. RESULTS: Two point mutations were identified in the present study, i.e., the p.Leu228X in one patient and p.Arg288Met in two patients. The mutation p.Arg288Met was first reported in Chinese and p.Leu228X was first reported in Mainland Chinese. The case carrying p.Leu228X mutation was diagnosed as SMA I with 2 copies of SMN2, and the cases with p.Arg288Met were diagnosed as SMA I and SMA II , respectively, with 3 copies of SMN2 gene. CONCLUSION: The mutations p.Leu228X and p.Arg288Met caused severe clinical phenotypes, SMA I or SMA II. This study suggested that the compound heterozygous mutations of SMN1 existed in Chinese SMA patients, which was rarely reported previously in Chinese. It was necessary to detect the point mutation in SMN1 for genetic diagnosis of those patients with heterozygous deletion of SMN1, which would be beneficial to prenatal diagnosis and genetic counseling in these families.

Differential Metabolites in Chinese Autistic Children: A Multi-Center Study Based on Urinary 1H-NMR Metabolomics Analysis.

Background: Autism spectrum disorder (ASD) is a group of early-onset neurodevelopmental disorders. However, there is no valuable biomarker for the early diagnosis of ASD. Our large-scale and multi-center study aims to identify metabolic variations between ASD and healthy children and to investigate differential metabolites and associated pathogenic mechanisms. Methods: One hundred and seventeen autistic children and 119 healthy children were recruited from research centers of 7 cities. Urine samples were assayed by 1H-NMR metabolomics analysis to detect metabolic variations. Multivariate statistical analysis, including principal component analysis (PCA), and orthogonal projection to latent structure discriminant analysis (OPLS-DA), as well as univariate analysis were used to assess differential metabolites between the ASD and control groups. The differential metabolites were further analyzed by receiver operating characteristics (ROC) curve analysis and metabolic pathways analysis. Results: Compared with the control group, the ASD group showed higher levels of glycine, guanidinoacetic acid, creatine, hydroxyphenylacetylglycine, phenylacetylglycine, and formate and lower levels of 3-aminoisobutanoic acid, alanine, taurine, creatinine, hypoxanthine, and N-methylnicotinamide. ROC curve showed relatively significant diagnostic values for hypoxanthine [area under the curve (AUC) = 0.657, 95% CI 0.588 to 0.726], creatinine (AUC = 0.639, 95% CI 0.569 to 0.709), creatine (AUC = 0.623, 95% CI 0.552 to 0.694), N-methylnicotinamide (AUC = 0.595, 95% CI 0.523 to 0.668), and guanidinoacetic acid (AUC = 0.574, 95% CI 0.501 to 0.647) in the ASD group. Combining the metabolites creatine, creatinine and hypoxanthine, the AUC of the ROC curve reached 0.720 (95% CI 0.659 to 0.777). Significantly altered metabolite pathways associated with differential metabolites were glycine, serine and threonine metabolism, arginine and proline metabolism, and taurine and hypotaurine metabolism. Conclusions: Urinary amino acid metabolites were significantly altered in children with ASD. Amino acid metabolic pathways might play important roles in the pathogenic mechanisms of ASD.

Psychometric properties of the Chinese Parent Version of the Autism Spectrum Rating Scale: Rasch analysis.

LAY ABSTRACT: The Autism Spectrum Rating Scale is a behavioural rating scale completed by parents and teachers that is useful for identifying children with an autism spectrum disorder. The development of a modified Autism Spectrum Rating Scale suitable for use in China is important for the identification of children in China with an autism spectrum disorder. In this study, we examined the Modified Chinese Autism Spectrum Rating Scale using a statistical technique known as Rasch analysis. Rasch analysis tests whether the questionnaire meets the standards for modern scientific measurement. We used Rasch analysis to examine data from 2013 children in China including 420 diagnosed with an autism spectrum disorder who had been rated by a parent or grandparent. After removing a small number of items (questions), the Modified Chinese Autism Spectrum Rating Scale met the stringent criteria for Rasch measurement. The availability of a reliable and precise tool for assessing behaviours characteristic of an autism spectrum disorder in Chinese children will improve the identification and diagnosis of autism spectrum disorder in China, thus enabling better provision of support services.

Prevalence of Autism Spectrum Disorder in China: A Nationwide Multi-center Population-based Study Among Children Aged 6 to 12 Years.

This study aimed to obtain the first national estimate of the prevalence of autism spectrum disorder (ASD) in Chinese children. We targeted the population of 6 to 12-year-old children for this prevalence study by multistage convenient cluster sampling. The Modified Chinese Autism Spectrum Rating Scale was used for the screening process. Of the target population of 142,086 children, 88.5% (n = 125,806) participated in the study. A total of 363 children were confirmed as having ASD. The observed ASD prevalence rate was 0.29% (95% CI: 0.26%-0.32%) for the overall population. After adjustment for response rates, the estimated number of ASD cases was 867 in the target population sample, thereby achieving an estimated prevalence of 0.70% (95% CI: 0.64%-0.74%). The prevalence was significantly higher in boys than in girls (0.95%; 95% CI: 0.87%-1.02% versus 0.30%; 95% CI: 0.26%-0.34%; P < 0.001). Of the 363 confirmed ASD cases, 43.3% were newly diagnosed, and most of those (90.4%) were attending regular schools, and 68.8% of the children with ASD had at least one neuropsychiatric comorbidity. Our findings provide reliable data on the estimated ASD prevalence and comorbidities in Chinese children.

Genetic analysis of four cases of methylmalonic aciduria and homocystinuria, cblC type#.

Methylmalonic aciduria and homocystinuria, cblC type, is the most common disorder of intracellular vitamin B12 (cobalamin, cbl) metabolism, which results in impaired biosynthesis of methylcobalamin and adenosylcobalamin. The gene MMACHC responsible for the cblC type had been identified, which enables molecular diagnostics. Here, we report four cblC type cases, which were identified by the typical manifestations, and a new approach of next-generation sequencing platform in pediatrics for genetic diseases, further confirmed by Sanger sequencing of the whole MMACHC gene. The article will replenish the mutational information of related genes to the cblC type, which makes for detecting of cblC disease through the newborn screening.

[Cognitive function of 172 cases of 6 - 13 years old children with epilepsy in regular school].

OBJECTIVE: To study the cognitive function, its correlation with and the impact on quality of life in epileptic children aged 6-13 years in regular school. METHOD: Cognitive function of 172 children with various types of epilepsy were measured using a computerized neuropsychological test battery including six items. Their scores across the neuropsychological measures were compared with 172 healthy control subjects from the general population strictly matched for age, sex and the region where education was accepted. The quality of life was measured in 105 cases by the Quality of Life in Epilepsy Inventory (QOLIE-31). RESULT: (1) After adjusting for age, gender, and education, children with epilepsy performed significantly worse than healthy control subjects on 5 of 6 cognitive tasks, including Raven's progressive matrices correct number (8.6 vs. 14.0), choice reaction time (620.4 ms vs. 489.5 ms), word-rhyming tasks (2796.9 ms vs. 2324.4 ms), simple substraction correct number (28.6 vs. 35.5)as well as number comparision (1002.4 ms vs. 803.1 ms), P < 0.01. When an impairment index was calculated, 44.2% patients had at least one abnormal score on the test battery, compared with 14.5% of healthy volunteers, there was statistically significant differences between the two groups, P < 0.001. (2) Children with new onset epilepsy before the treatment with anti-epilepstic drugs performed significantly worse than healthy controls on 5 of 6 cognitive tasks, including Raven's progressive matrices correct number (9.1 vs. 13.8), choice reaction time (625.8 ms vs.474.5 ms), word-rhyming tasks(3051.8 ms vs. 2575.4 ms), simple substraction correct number (28.9 vs. 35.3) as well as number comparison (942.4 ms vs. 775.8 ms), P < 0.01. (3) Cognitive performance was not related to the age of onset, type of epilepsy, therapy duration or comorbid emotional and behavior disorders, P > 0.05. (4) 105 cases filled in the QOLIE-31 questionaire, the total score of the quality of life in the group without cognitive impairment and psychical conditions was the highest (60.5 ± 0.9), and the lowest total score was found in group with cognitive impairment and psychical conditions (54.6 ± 1.5), there were highly significant differences between the groups, P < 0.001. CONCLUSION: Almost one-half of the children with epilepsy accepting regular education had at least one abnormal score in the battery tests. Newly diagnosed untreated patients with epilepsy are cognitively compromised before the start of antiepileptic drug medication. Cognitive impairment was not related to the epilepsy-related or psychiatric variables. Cognitive impairment and mental disorders require further attention and essential therapy, which is important to the improvement of the quality of life in epileptic children.

[Mutation analysis of SMN1 gene in patients with spinal muscular atrophy].

OBJECTIVE: Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder. About 80% - 90% of SMA patients are missing both copies of SMN1, and 5% - 10% of patients are compound heterozygotes. In the present study, we aimed to analyze survival motor neuron 1 (SMN1) gene mutation in three patients with spinal muscular atrophy and their families to explore the effect of mutation on SMN protein function and the relationship between mutation and clinical phenotype. METHOD: According to the international criterion, all patients were diagnosed by a neurologist. Patient 1 is a 5 years old boy with SMA type II. Patient 2, female, 2.5 years old, was SMA type II. Patient 3, female, 9 years old, was SMA type III. The brother of patient 3 was SMA type II, too. The age at last examination was 14 years. Genomic DNA was extracted from peripheral blood leukocytes by using standard phenol/chloroform method and total RNA was extracted from whole blood with QIAamp RNA Blood Mini Kit. PCR/RFLP was used to detect the homozygosis deletion of the SMN1 exon 7, and multiplex ligation-dependent probe amplification (MLPA) were performed to analyze the gene dosage of SMN1 and SMN2 for each patient and his/her family members; reverse transcriptase (RT)-PCR and clone sequencing were conducted for identifying the point mutation of SMN1 in three patients. The sequencing of genomic DNA and MLPA were carried out in the 3 families members to confirm the transition of mutation. RESULT: No homozygous deletion of the SMN1 exon 7 was observed in any member of the 3 families. Case 1 and case 2 had one SMN1 copy compound with c.400G > A (p.Glu134Lys) mutation on it and SMN2 was two copies, respectively. Case 3 and her brother also had one copy of SMN1 and two copies of SMN2, and a mutation c.689C > T (p.Ser230Leu) occurred on the retained SMN1. All point mutations were from their fathers and deletion come from their mothers for SMN1 gene. CONCLUSION: In this work, p.Glu134Lys and p.Ser230Leu mutations were identified in three unrelated families and p.Glu134Lys from two patients was first discovered in Chinese SMA. The p.Glu134Lys mutation within the SMN Tudor domain prevents the binding of SMN and Sm. The fact that p.Ser230Leu results in a polar amino acid substituted for non-polar amino acid possibly affects the structure of SMN and then damages its function. SMN1 point mutation analysis is not only advantageous to the diagnosis of those patients with heterozygous deletion of SMN1, but will be beneficial to the prenatal diagnosis and genetic counseling for their families.

[Emotional and behavioral comorbidities and the impact on the quality of life in epilepsy children].

OBJECTIVE: To find out the rate of comorbidities of depression, anxiety disorder and attention deficit hyperactivity disorder (ADHD) symptoms in children with epilepsy and to analyze the relevant affecting factors and impacts on quality of life. METHOD: Totally 142 children with various types of epilepsy underwent neuropsychological assessment with the Depression Self-rating Scale for Children, the Screen for Child Anxiety Related Emotional Disorders and the ADHD Rating Scale-IV, an 18-item parent-rated questionnaire based on the diagnostic criteria for ADHD, the quality of life was measured in 100 cases on antiepileptic medications by the Quality of Life in Epilepsy Inventory (QOLIE-31). The comorbidity rates were calculated using t-test, chi(2) test and multiple logistic analysis, the variables associated with psychiatric comorbidities were determined, and the impact on quality of life was analyzed. RESULT: (1) The total rate of emotional and behavioral comorbidities was 57.7% (82/142), the frequency of depressive disorder, anxiety disorder and ADHD was 14.8%, 44.4% and 17.6%, respectively. The suicidal ideation occasionally occurred in 5.6% of the cases and 0.7% of cases often had the ideation, but no suicidal action was found in any case. (2) Risk factors for the emotional and behavioral disorders: multiple logistic analysis indicated that age, gender and epilepsy illness-related variables were not relative to the comorbidities, P > 0.05, there were interactions among the disorders. (3) The impact on the quality of life: The emotional and behavioral conditions were associated with the low quality of life, which was significantly lower in epileptic children with co-morbid disorder compared to non-comorbidities epilepsy group. Especially negative impact on the total score of quality of life and four sub-items such as overall quality, emotional well-being, cognitive and social function, P < 0.001. There were also significant differences between the two groups in the other three sub-items including fear for seizure attack, energy/fatigue and medication effects (P < 0.05). CONCLUSIONS: The frequency of emotional and behavioral disorders including depress disorder, anxiety disorder and ADHD was considerably high in children with epilepsy. Age, gender and epilepsy illness-related variables are not associated with the emotional and behavioral comorbidities, which interfere with each other. Emotional and behavioral disorder is one of the negative factors to the quality of life in epileptic patients. Neuropsychological assessment and treatment are important for improvement of the quality of life in children with epilepsy.