Discovery of specific mutations in spinal muscular atrophy patients by next-generation sequencing.

Spinal muscular atrophy (SMA) is a type of autosomal recessive genetic disease, which seriously threatens the health and lives of children and adolescents. We attempted to find some genes and mutations related to the onset of SMA. Eighty-three whole-blood samples were collected from 28 core families, including 28 probands with clinically suspected SMA (20 SMA patients, 5 non-SMA children, and 3 patients with unknown etiology) and their parents. The multiplex ligation probe amplification (MLPA) was performed for preliminary diagnosis. The high-throughput sequencing technology was used to conduct the whole-exome sequencing analysis. We analyzed the mutations in adjacent genes of SMN1 gene and the unique mutations that only occurred in SMA patients. According to the MLPA results, 20 probands were regarded as experimental group and 5 non-SMA children as control group. A total of 10 mutations were identified in the adjacent genes of SMN1 gene. GUSBP1 g.[69515863G>A], GUSBP1 g.[69515870C>T], and SMA4 g.[69515738C>A] were the top three most frequent sites. SMA4 g.[69515726A>G] and OCLN c.[818G>T] have not been reported in the existing relevant researches. Seventeen point mutations in the DYNC1H1 gene were only recognized in SMA children, and the top two most common mutations were c.[2869-34A>T] and c.[345-89A>G]; c.[7473+105C>T] was the splicing mutation that might change the mRNA splicing site. The mutations of SMA4 g.[69515726A>G], OCLN c.[818G>T], DYNC1H1 c.[2869-34A>T], DYNC1H1 c.[345-89A>G], and DYNC1H1 c.[7473+105C>T] in the adjacent genes of SMN1 gene and other genes might be related to the onset of SMA.

[Molecular epidemiology of norovirus in children with acute gastroenteritis in Tianjin, China].

OBJECTIVE: To investigate the molecular epidemiological characteristics of norovirus (NoV) among children with acute gastroenteritis in Tianjin in 2017. METHODS: A total of 758 stool specimens were collected from the children with acute gastroenteritis possibly caused by viral infection in Tianjin Children's Hospital between January and December, 2017. Quantitative real-time RT-PCR was used for primary screening of NoV, and conventional RT-PCR was used for gene amplification, sequencing and genotype identification of the VP1 region of capsid protein in positive specimens. RESULTS: Among the 758 specimens, 241 (31.8%) were found to have GII NoV. Sequencing of the VP1 region of capsid protein in positive specimens showed that among the 241 specimens with GII NoV, 69 (28.6%) had GII.4 subtype, 51 (21.2%) had GII.3 subtype, 24 (10.0%) had GII.2 subtype, and 18 (7.5%) had other subtypes. There was a significant difference in NoV detection rate between different age groups (P=0.018), and the 1- <4 years group had the highest NoV detection rate (37.3%). There was also a significant difference in NoV detection rate across seasons (P<0.001), and there was a highest NoV detection rate in winter (48.1%). Twenty-seven children (3.6%) had co-infections with NoV and rotavirus. CONCLUSIONS: NoV is one of the major pathogens of the children with acute gastroenteritis from Tianjin in 2017. GII genotype, especially GII.4 subtype, is the prevalent strain. NoV infection is commonly seen in children less than 4 years and reaches the peak in winter. Some children are found to have co-infections with rotavirus.

Choroid Plexus Papilloma of Bilateral Lateral Ventricle in an Infant Conceived by in vitro Fertilization.

Choroid plexus papilloma (CPP) is a rare benign tumor of the central nervous system. Bilateral lateral ventricle CPP is extremely uncommon. In this case report, we described a case of bilateral lateral ventricle CPP in a 4-month-old female patient conceived by in vitro fertilization (IVF). Neurological examination and imaging were performed. In neurological examination, meningeal irritation signs and sunset phenomenon were positive. Brain computed tomography (CT) and magnetic resonance imaging (MRI) displayed masses located in the trigone of the bilateral lateral ventricle with hydrocephalus. Contrast-enhanced MRI showed intense homogeneous enhancement. The diagnoses of bilateral lateral ventricle CPP related to hydrocephalus and extravasation of cerebrospinal fluid (CSF) were made. Repeated surgical procedures via parietotemporal craniotomy were performed, and the diagnosis was confirmed by histopathology examination. The patient presented with delayed development during a follow-up period of 1 year. In conclusion, imaging is an effective approach of investigation. CPP could be highly suspected according to the features of hydrocephalus, lobulated appearance, and homogeneous enhancement on imaging. Total surgical removal is a valid curative method for CPP.

[A molecular epidemiological study of KI polyomavirus and WU polyomavirus in children with acute respiratory infection in Tianjin, China].

OBJECTIVE: To investigate the relationship of KI polyomavirus (KIPyV) and WU polyomavirus (WUPyV) with acute respiratory infection in children in Tianjin, China. METHODS: A total of 3 730 nasopharyngeal secretions were collected from hospitalized children with acute respiratory infection in Tianjin Children's Hospital from January 2011 to December 2013. Viral nucleic acid was extracted, and virus infection (KIPyV and WUPyV) was determined by PCR. Some KIPyV-positive and WUPyV-positive PCR products were subjected to sequencing. Sequencing results were aligned with the known gene sequences of KIPyV and WUPyV to construct a phylogenetic tree. Amplified VP1 fragments of KIPyV were inserted into the cloning vector (PUCm-T) transformed into E. coli competent cells. Positive clones were identified by PCR and sequencing. The nucleotide sequences were submitted to GenBank. In addition, another seven common respiratory viruses in all samples were detected by direct immunofluorescence assay. RESULTS: In the 3 730 specimens, the KIPyV-positive rate was 12.14% (453/3 730) and the WUPyV-positive rate was 1.69% (63/3 730). The mean infection rate of KIPyV was significantly higher in June and July, while the mean infection rate of WUPyV peaked in February and March. Most of the KIPyV-positive or WUPyV-positive children were <3 years. The co-infections with KIPyV, WUPyV, and other respiratory viruses were observed in the children. The co-infection rate was 2.31% (86/3 730) and there were nine cases of co-infections with WUPyV and KIPyV. Thirty-five KIPyV-positive and twelve WUPyV-positive PCR products were sequenced and the alignment analysis showed that they had high homology with the known sequences (94%-100% vs 95%-100%). The VP1 gene sequences obtained from two KIPyV strains in this study were recorded in GenBank with the accession numbers of KY465925 and KY465926. CONCLUSIONS: For some children with acute respiratory infection in Tianjin, China, the acute respiratory infection may be associated with KIPyV and WUPyV infections. KIPyV infection is common in summer, and WUPyV infection in spring. The epidemic strains in Tianjin have a high homology with those in other regions.

Intracranial Medulloepithelioma in a Child: A Case Report.

Intracranial medulloepithelioma is an extremely rare and highly malignant fast-growing tumor that shows a propensity to spread widely throughout the central nervous system. It most commonly occurs in infants and young children. We report a rare case of 2-year-old female patient with a large mass lesion diagnosed as medulloepithelioma. Although radiological examination was characteristic for the neoplasm, it was not sufficient to make a definite diagnosis. However, when it was combined with histopathological examination, we could diagnose medulloepithelioma and differentiate it from other central nervous system tumors. We intend to provide greater understanding and knowledge of intracranial medulloepithelioma by reporting this case.

Immature teratoma of the posterior fossa in an infant: case report.

Teratoma is a rare tumor of the central nervous system that belongs to intracranial germ cell tumors. We report a 2-month-old male child with an immature teratoma of the posterior fossa. Physical and laboratory examinations were normal. Though a radiologic examination was characteristic for this neoplasm, it was insufficient to make a definite diagnosis. Combining the radiologic findings with a histopathologic examination contributed to diagnosing immature teratoma and differentiating it from other subtypes of intracranial germ cell tumors. Our aim was to provide a greater understanding of immature teratoma by reporting this case.

Teratom, merkezi sinir sisteminin nadir görülen bir tümörü olup intrakranial germ hücreli tümörlerden birisidir. Bu makalede, posterior fossanin immatür teratomu bulunan 2 aylik bir erkek çocugu sunmaktayiz. Fizik baki ve laboratuvar bulgulari normal saptandi. Radyolojik inceleme bu neoplazma açisindan belirgin bulunmasina ragmen, kesin tani koymak için yetersizdi. Radyolojik bulgularin histopatolojik inceleme ile birlestirilmesi, immatür teratomun tanisina ve immatür teratomun intrakraniyal germ hücreli tümörlerinin diger alt türlerinden ayirt edilmesine katkida bulunmustur. Bu olguyu sunarak, immatür teratomun daha iyi anlasilmasini saglamayi amaçladik.

A novel mutation in a common pathogenic gene (SETD5) associated with intellectual disability: A case report.

Intellectual disability (ID) is a non-specific phenotype present in a genetically heterogeneous group of disorders. The genetic cause of ID remains elusive in the majority of patients due to this extreme heterogeneity. Whole exome sequencing technology has been applied to identify pathogenic gene variants responsible for ID. The present report described a 1.7-year-old female patient who had severe ID with the specific features of delayed motor development, language disorders and abnormal facial features. Exome analysis identified a novel pathogenic variant of the SETD5 gene [c.2025_2026delAG (p.Gly676Valfs*2)]. The variant was a frameshift mutation, causing termination of the protein in advance. These findings indicated that this mutation of the SETD5 gene may be a genetic cause for ID. The present study aimed to provide a meaningful exploration of ID and the identification of clinical core genetic pedigrees.

Association of neural tube defects with maternal alterations and genetic polymorphisms in one-carbon metabolic pathway.

BACKGROUND: Neural tube defects (NTDs) are birth defects of the brain, spine, or spinal cord invoked by the insufficient intake of folic acid in the early stages of pregnancy and have a complex etiology involving both genetic and environmental factors. So the study aimed to explore the association between alterations in maternal one-carbon metabolism and NTDs in the offspring. METHODS: We conducted a case-control study to get a deeper insight into this association, as well as into the role of genetic polymorphisms. Plasma concentrations of folate, homocysteine (Hcy), S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH) and genotypes and alleles distributions of 52 SNPs in 8 genes were compared for 61 women with NTDs-affected offspring and 61 women with healthy ones. RESULTS: There were significant differences between groups with regard to plasma folate, SAM, SAH and SAM/SAH levels. Logistic regression results revealed a significant association between maternal plasma folate level and risk of NTDs in the offspring. For MTHFD1 rs2236225 polymorphism, mothers having GA genotype and A allele exhibited an increased risk of NTDs in the offspring (OR = 2.600, 95%CI: 1.227-5.529; OR = 1.847, 95%CI: 1.047-3.259). For MTHFR rs1801133 polymorphism, mothers having TT and CT genotypes were more likely to affect NTDs in the offspring (OR = 4.105, 95%CI: 1.271-13.258; OR = 3.333, 95%CI: 1.068-10.400). Moreover, mothers carrying T allele had a higher risk of NTDs in the offspring (OR = 1.798, 95%CI: 1.070-3.021). For MTRR rs1801394 polymorphism, the frequency of G allele was significantly higher in cases than in controls (OR = 1.763, 95%CI: 1.023-3.036). Mothers with NTDs-affected children had higher AG genotype in RFC1 rs1051226 polymorphism than controls, manifesting an increased risk for NTDs (OR = 3.923, 95%CI: 1.361-11.308). CONCLUSION: Folic acid deficiency, MTHFD1 rs2236225, MTHFR rs1801133, MTRR rs1801349 and RFC1 rs1051226 polymorphisms may be maternal risk factors of NTDs.