Analysis of genome copy number variations in fetuses with isolated ventricular septal defect and a literature review / 中华医学遗传学杂志

OBJECTIVE@#To assess the value of copy number variation sequencing (CNV-seq) for revealing the genetic etiology of fetuses with isolated ventricular septal defect (VSD).@*METHODS@#From December 2017 to December 2020, 69 fetuses with isolated VSD were identified at the First Affiliated Hospital of Zhengzhou University. Meanwhile, 839 similar prenatal cases were selected from public databases including Wanfang data, Wanfang Medicine, and China National Knowledge Infrastructure (CNKI) by using keywords such as "Ventricular septal defect", "Copy number variation", and "Prenatal". A total of 908 fetuses with isolated VSD were analyzed. CNV-seq was carried out for 69 fetuses.@*RESULTS@#Among the 908 fetuses, 33 (3.63%) were found to harbor pathogenic CNVs, which included 11 chromosomal aneuploidies (1.21%) and 22 pathogenic CNVs (2.42%). The pathogenic CNVs have involved 12 genetic syndromes, with those known to involve the heart development including 5 cases of 22q11.21 deletion syndrome, 2 cases of 4q terminal deletion syndrome, and 1 case of 9q subtelomere deletion syndrome. The outcome of pregnancies for 15 fetuses with pathogenic CNVs was known, of which 12 were terminated, and 3 had spontaneous closure of the ventricular septum after birth, but 1 of them had other abnormalities.@*CONCLUSION@#Fetuses with isolated VSD have a relatively high risk for chromosomal abnormalities, for which CNV-seq should be recommended.

Analysis of a child with autosomal dominant mental retardation type 40 due to variant of CHAMP1 gene / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical and genetic features of a child with autosomal dominant mental retardation type 40 (MRD40) due to variant of the CHAMP1 gene.@*METHODS@#Clinical characteristics of the child were analyzed. Genetic testing was carried out by low-depth high-throughput and whole genome copy number variant sequencing (CNV-seq) and whole exome sequencing (WES). A literature review was also carried out for the clinical phenotype and genetic characteristics of patients with MRD40 due to CHAMP1 gene variants.@*RESULTS@#The child, a 11-month-old girl, has presented with intellectual and motor developmental delay. CNV-seq revealed no definite pathogenic variants. WES has detected the presence of a heterozygous c.1908C>G (p.Y636*) variant in the CHAMP1 gene, which was carried by neither parent and predicted to be pathogenic. Literature review has identified 33 additional children from 12 previous reports. All children had presented with developmental delay and mental retardation, and most had dystonia (94.1%), delayed speech and/or walking (85.2%, 82.4%) and ocular abnormalities (79.4%). In total 26 variants of the CHAMP1 gene were detected, with all nonsense variants being of loss-of-function type, located in exon 3, and de novo in origin.@*CONCLUSION@#The heterozygous c.1908C>G (p.Y636*) variant of the CHAMP1 gene probably underlay the WRD40 in this child. Genetic testing should be considered for children featuring global developmental delay, mental retardation, hypertonia and facial dysmorphism.

Clinical application of non-invasive prenatal diagnosis of phenylketonuria based on haplotypes via paired-end molecular tags and weighting algorithm.

BACKGROUND: Phenylketonuria (PKU) is a metabolic disease that can cause severe and irreversible brain damage without treatment. METHODS: Here we developed a non-invasive prenatal diagnosis (NIPD) technique based on haplotypes via paired-end molecular tags and weighting algorithm and applied it to the NIPD of PKU to evaluate its accuracy and feasibility in the early pregnancy. A custom-designed hybridization probes containing regions in phenylalanine hydroxylase (PAH) gene and its 1 Mb flanking region were used for target sequencing on genomic and maternal plasma DNA (7-13 weeks of gestation) to construct the parental haplotypes and the proband's haplotype. Fetal haplotype was then inferred combined with the parental haplotypes and the proband's haplotype. The presence of haplotypes linked to both the maternal and paternal mutant alleles indicated affected fetuses. The fetal genotypes were further validated by invasive prenatal diagnosis in a blinded fashion. RESULTS: This technique has been successfully applied in twenty-one cases. Six fetuses were diagnosed as patients carrying both of the mutated haplotypes inherited from their parents. Eleven fetuses were carriers of one heterozygous PAH variants, six of which were paternal and five of which were maternal. Four fetuses were absence of pathogenic alleles. All results were consistent with the prenatal diagnosis through amniotic fluid. CONCLUSIONS: The results showed that our new technique applied to the genotyping of fetuses with high risk for PKU achieves an accurate detection at an early stage of pregnancy with low fetal fraction in cell free DNA.

Analysis of a case with heterozygous 14q12 deletion and FOXG1 gene-related disease / 中华医学遗传学杂志

OBJECTIVE@#To describe the clinical and genetic characteristics of a child with 14q12q13.1 deletion involving the FOXG1 gene.@*METHODS@#Clinical manifestation of the child was analyzed. Peripheral blood sample of the patient was subjected to chromosomal karyotyping and single nucleotide polymorphism array (SNP-array) analysis.@*RESULTS@#The male infant has developed feeding difficulty, poor sucking, lower limb tremor, and frontal bruising 8 days after birth. Magnetic resonance imaging revealed significant enlargement of bilateral ventricles and corpus callosum dysplasia. Chromosomal analysis revealed a karyotype of 46,XY,del(14)(q12q13.1), and SNP-array confirmed that there was a 9.6 Mb deletion in 14q11.2q13.1, which encompassed the FOXG1 gene.@*CONCLUSION@#For patients with brain development abnormalities, dyskinesia, cognitive impairment, speech disorder and other manifestations, copy number variation of the FOXG1 gene should be excluded. SNP-array should be carried out as early as possible to attain the diagnosis.

Epidemiological investigation and prevention control analysis of longitudinal distribution of COVID-19 in Henan province, China

ObjectiveTo analyze the vertical distribution of six cities in Henan Province,China from January 21, 2020 to June17, 2020: Xinyang City (including Gushi County), Nanyang City (including Dengzhou City), Zhumadian City (including XincaiCounty), Zhengzhou City (including Gongyi City), Puyang City and Anyang City (including Hua County) corona virus disease 2019(COVID-19) epidemiological characteristics and local prevention and control measures. MethodsData were collected and analyzed through the COVID-19 information published on the official websites of health commissions of Henan Province and six cities. ResultsAs of June 17, 2020, the cumulative incidence rate of COVID-19 in Henan province was 1.33/100,000, the cumulative cure rate was 98.27%, the cumulative mortality rate was 1.73%, the age range of diagnosed cases was 5days-85years old, and the male to female ratio was 1.09:1.The confirmed cases of COVID-19 in Henan province were mainly imported cases from Hubei, accounting for 87.74%, of which the highest number was 70.50% in Zhumadian. The contact cases and local cases increased in a fluctuating manner over time. SignificanceIn this paper, epidemiological characteristics of COVID-19 in Henan province from the outbreak to the effective control within 60 days were analyzed, and effective and distinctive prevention and control measures in various cities were summarized, so as to provide a favorable reference for the further formulation and implementation of epidemic prevention and control and a valuable theoretical basis for effectively avoiding the second outbreak. ImportanceEpidemic prevention and control in China has entered the normalized this new stage, this article analyze the epidemiological characteristics of COVID - 19 in henan province, and summarizes the prefecture level and effective disease prevention and control means and measures, the normalized private provide the theoretical reference to the prevention and control work, formulate and carry out, at the same time in other countries and regions of epidemic prevention and control work can also be used for reference.

Progress of research on induced pluripotent stem cell models for Down syndrome / 中华医学遗传学杂志

With an incidence of 1/800 - 1/600, Down syndrome (DS) is the most common chromosomal disorder in humans. Whilst most DS patients has trisomy 21, a small proportion may carry translocations or mosaicisms involving chromosome 21. The main characteristics of DS include mental retardation, peculiar facies, growth retardation, congenital heart disease, duodenal stenosis, Alzheimer's disease, leukemia, and immunodeficiency, which may be due to increased dosage of critical genes. Recent studies also showed that epigenetic changes may also occur in DS. For research on patients with DS or other trisomies have been restricted by ethical considerations, and commonly used mouse models cannot fully replicate the characteristic features of DS, pluripotent stem cells induced from fetal samples or biopsy tissues from DS patients may generate models with the same genetic content, which may provide idea materials for studying the pathogenesis of DS and customized cell and/or gene therapies.

Mechanisms of nodule-specific melanization in the hemocoel of the silkworm, Bombyx mori.

In the insect immune system, nodules are known to be a product of the cellular response against microorganisms and may be a preferential target for melanization. However, the mechanism of nodule-preferential melanization remains to be explored. In this study, we identified several mechanisms of nodule-preferential melanization by analyzing congregation and the activation of several factors involved in the prophenoloxidase (proPO)-activating system in the silkworm, Bombyx mori. Microorganism-binding assays revealed that B. mori larval plasma have an effective invading microorganism-surveillance network consisting of at least six pattern-recognition receptors (PRRs). We also found that a hemolymph serine proteinase, BmHP14, can bind to Saccharomyces cerevisiae. Pull-down assays showed that PRR C-type lectins form protein complexes with serine proteinase homologs, BmSPH1 and BmSPH2, which leads to the activated forms of BmSPH1 and BmSPH2 being gathered on microorganisms and trapped in nodules. Immunostaining analysis revealed that most factors in the proPO-activating system and some factors in the triggering system for antimicrobial peptide production exist in the granules of hemocytes which can gather in nodules. Western blot analysis showed that factors in the proPO-activating system are congregated in formed nodules by their concentration in plasma and aggregating hemocytes.

Factors functioning in nodule melanization of insects and their mechanisms of accumulation in nodules.

Nodules consisting of hemocytes and trapped microorganisms are important targets for melanization, which is best known in the insect immune system. We investigated factors functioning in nodule melanization and the mechanism by which these factors congregate in the nodule. BmHP21, BmSPH1 and BmSPH2, Bombyx mori orthologs of Manduca sexta serine protease HP21, serine protease homologs (SPH1 and SPH2), and a prophenoloxidase, BmPO1 were observed as inactive forms in the plasma, but as putatively active forms in the nodule. Production of prophenoloxidase-activating proteinases, BmPAP1 and BmPAP3/PPAE and BmPO1 were confirmed in hemocytes. BmSPH1 and BmSPH2 were observed on trapped bacterial cells in the nodule and were isolated from the surface of bacterial cells incubated with plasma. BmSPH1 and BmSPH2 were found in plasma in complex with a pattern recognition receptor, BmLBP. These data suggest that melanization-regulating factors congregate in nodules through a combination of microorganism-dependent and hemocyte-dependent routes.