First Report ofCTNSMutations in a Chinese Family with Infantile Cystinosis

Infantile cystinosis (IC) is a rare autosomal recessive disorder characterized by a defect in the lysosomal-membrane transport protein, cystinosin. It serves as a prototype for lysosomal transport disorders. To date, severalCTNSmutations have been identified as the cause of the prototypic disease across different ethnic populations worldwide. However, in Asia, theCTNSmutation is very rarely reported. For the Chinese population, no literature onCTNSmutation screening for IC is available to date. In this paper, by using the whole exome sequencing and Sanger sequencing, we identified two novelCTNSsplicing deletions in a Chinese IC family, one at the donor site of exon 6 ofCTNS(IVS6+1, del G) and the other at the acceptor site of exon 8 (IVS8-1, del GT). These data give information for the genetic counseling of the IC that occurred in Chinese population.

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Case report: two novel VPS13B mutations in a Chinese family with Cohen syndrome and hyperlinear palms

BMC Medical Genetics ◽

10.1186/s12881-019-0920-x ◽

2019 ◽

Vol 20 (1) ◽

Cited By ~ 3

Author(s):

Sha Zhao ◽

Zhenqing Luo ◽

Zhenghui Xiao ◽

Liping Li ◽

Rui Zhao ◽

...

Keyword(s):

Developmental Delay ◽

Chinese Population ◽

Autosomal Recessive ◽

Autosomal Recessive Disorder ◽

Chinese Family ◽

Compound Heterozygous ◽

Case Presentation ◽

Cohen Syndrome ◽

The Family ◽

Sporadic Cases

Abstract Background Cohen syndrome (CS) is an uncommon developmental disease with evident clinical heterogeneity. VPS13B is the only gene responsible for CS. Only few sporadic cases of CS have been reported in China. Case presentation A Chinese family with two offspring–patients affected by developmental delay and intellectual disability was investigated in this study. Exome sequencing was performed, and compound heterozygous mutations in VPS13B were segregated for family members with autosomal recessive disorder. Splicing mutation c.3666 + 1G > T (exon 24) and nonsense mutation c. 9844 A > T:p.K3282X (exon 54) were novel. We revisited the family and learned that both patients are affected by microcephaly, developmental delay, neutropenia, and myopia and have a friendly disposition, all of which are consistent with CS phenotypes. We also found that both patients have hyperlinear palms, which their parents do not have. VPS13B mutations reported among the Chinese population were reviewed accordingly. Conclusions This study presents two novel VPS13B mutations in CS. The identification of hyperlinear palms in a family affected by CS expands the phenotype spectrum of CS.

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Whole exome sequencing identifies a splicing mutation in NSUN2 as a cause of a Dubowitz-like syndrome

Journal of Medical Genetics ◽

10.1136/jmedgenet-2011-100686 ◽

2012 ◽

Vol 49 (6) ◽

pp. 380-385 ◽

Cited By ~ 128

Author(s):

Fernando Jose Martinez ◽

Jeong Ho Lee ◽

Ji Eun Lee ◽

Sandra Blanco ◽

Elizabeth Nickerson ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

United Arab Emirates ◽

Rna Splicing ◽

Cytosine Methylation ◽

Autosomal Recessive Disorder ◽

Splice Acceptor Site ◽

Acceptor Site ◽

Site Specific ◽

Whole Exome

BackgroundDubowitz syndrome (DS) is an autosomal recessive disorder characterized by the constellation of mild microcephaly, growth and mental retardation, eczema and peculiar facies. Over 140 cases have been reported, but the genetic basis is not understood.MethodsWe enrolled a multiplex consanguineous family from the United Arab Emirates with many of the key clinical features of DS as reported in previous series. The family was analyzed by whole exome sequencing. RNA splicing was evaluated with reverse-transcriptase PCR, immunostaining and western blotting was performed with specific antibodies, and site-specific cytosine-5-methylation was studied with bisulfite sequencing.ResultsWe identified a homozygous splice mutation in the NSUN2 gene, encoding a conserved RNA methyltransferase. The mutation abolished the canonical splice acceptor site of exon 6, leading to use of a cryptic splice donor within an AluY and subsequent mRNA instability. Patient cells lacked NSUN2 protein and there was resultant loss of site-specific 5-cytosine methylation of the tRNA(Asp GTC) at C47 and C48, known NSUN2 targets.ConclusionOur findings establish NSUN2 as the first causal gene with relationship to the DS spectrum phenotype. NSUN2 has been implicated in Myc-induced cell proliferation and mitotic spindle stability, which might help explain the varied clinical presentation in DS that can include chromosomal instability and immunological defects.

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IFNAR1 gene mutation may contribute to developmental stuttering in the Chinese population

Hereditas ◽

10.1186/s41065-021-00211-y ◽

2021 ◽

Vol 158 (1) ◽

Author(s):

Yimin Sun ◽

Yong Gao ◽

Yuxi Zhou ◽

Yulong Zhou ◽

Ying Zhang ◽

...

Keyword(s):

Candidate Genes ◽

Chinese Population ◽

Sanger Sequencing ◽

Chinese Family ◽

Type I ◽

Chinese Families ◽

Whole Exome ◽

Persistent Developmental Stuttering ◽

Sporadic Cases ◽

Developmental Stuttering

Abstract Background Developmental stuttering is the most common form of stuttering without apparent neurogenic or psychogenic impairment. Recently, whole-exome sequencing (WES) has been suggested to be a promising approach to study Mendelian disorders. Methods Here, we describe an application of WES to identify a gene potentially responsible for persistent developmental stuttering (PDS) by sequencing DNA samples from 10 independent PDS families and 11 sporadic cases. Sanger sequencing was performed for verification with samples obtained from 73 additional patients with sporadic cases. Results We first searched for cosegregating variants/candidate genes in a Chinese family (Family 0) by sequencing DNA obtained from 3 affected members and 3 controls. Next, we sequenced DNA samples obtained from 9 additional Chinese families (Families 1-9) with stuttering to verify the identified candidate genes. Intriguingly, we found that two missense variants (Leu552Pro and Lys428Gln) of interferon-alpha/beta receptor 1 (IFNAR1) cosegregated with stuttering in three independent families (Families 0, 5 and 9). Moreover, we found two additional mutations (Gly301Glu and Pro335del) in the IFNAR1 gene in 4 patients with sporadic cases by using WES or Sanger sequencing. Further receptor mutagenesis and cell signaling studies revealed that these IFNAR1 variants may impair the activity of type I IFN signaling. Conclusion Our data indicate that IFNAR1 might be a potential pathogenic gene of PDS in the Chinese population.

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A novel TLE6 mutation, c.541+1G>A, identified using whole‐exome sequencing in a Chinese family with female infertility

Molecular Genetics & Genomic Medicine ◽

10.1002/mgg3.1743 ◽

2021 ◽

Author(s):

Bin Mao ◽

Xueling Jia ◽

Hongfang Liu ◽

Xiaojuan Xu ◽

Xiaodong Zhao ◽

...

Keyword(s):

Exome Sequencing ◽

Whole Exome Sequencing ◽

Female Infertility ◽

Chinese Family ◽

Whole Exome

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A Novel Mutation in COL4A1 Gene in a Chinese Family with Pontine Autosomal Dominant Microangiopathy and Leukoencephalopathy

Translational Stroke Research ◽

10.1007/s12975-021-00926-0 ◽

2021 ◽

Author(s):

Qing Li ◽

Chengfeng Wang ◽

Wei Li ◽

Zaiqiang Zhang ◽

Shanshan Wang ◽

...

Keyword(s):

Basement Membrane ◽

Skin Biopsy ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Autosomal Dominant ◽

Chinese Family ◽

Heterozygous Mutation ◽

Collagen Type Iv ◽

Lacunar Infarcts ◽

Whole Exome

AbstractPontine autosomal dominant microangiopathy and leukoencephalopathy (PADMAL) is a rare hereditary cerebral small vessel disease. We report a novel collagen type IV alpha 1 (COL4A1) gene mutation in a Chinese family with PADMAL. The index case was followed up for 6 years. Neuroimaging, whole-exome sequencing, skin biopsy, and pedigree analysis were performed. She initially presented with minor head injury at age 38. MRI brain showed chronic lacunar infarcts in the pons, left thalamus, and right centrum semiovale. Extensive workup was unremarkable except for a patent foramen ovale (PFO). Despite anticoagulation, PFO closure, and antiplatelet therapy, the patient had recurrent lacunar infarcts in the pons and deep white matter, as well as subcortical microhemorrhages. Whole-exome sequencing demonstrated a novel c.*34G > T mutation in the 3′ untranslated region of COL4A1 gene. Skin biopsy subsequently demonstrated thickening of vascular basement membrane, proliferation of endothelial cells, and stenosis of vascular lumen. Three additional family members had gene testing and 2 of them were found to have the same heterozygous mutation. Of the 18 individuals in the pedigree of 3 generations, 12 had clinical and MRI evidence of PADMAL. The mechanisms of both ischemic and hemorrhagic stroke are likely the overexpression of COLT4A1 in the basement membrane and frugality of the vessel walls. Our findings suggest that the novel c.*34G > T mutation appears to have the same functional consequences as the previously reported COL4A1 gene mutations in patients with PADMAL and multi-infarct dementia of Swedish type.

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Rare Variants in Autophagy and Non-Autophagy Genes in Late-Onset Pompe Disease: Suggestions of Their Disease-Modifying Role in Two Italian Families

International Journal of Molecular Sciences ◽

10.3390/ijms22073625 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3625

Author(s):

Filomena Napolitano ◽

Giorgia Bruno ◽

Chiara Terracciano ◽

Giuseppina Franzese ◽

Nicole Piera Palomba ◽

...

Keyword(s):

Pompe Disease ◽

Rare Variants ◽

Clinical Symptoms ◽

Late Onset ◽

Respiratory Muscles ◽

Autosomal Recessive Disorder ◽

Compound Heterozygous ◽

Enzyme Replacement ◽

Whole Exome ◽

Clinical Pictures

Pompe disease is an autosomal recessive disorder caused by a deficiency in the enzyme acid alpha-glucosidase. The late-onset form of Pompe disease (LOPD) is characterized by a slowly progressing proximal muscle weakness, often involving respiratory muscles. In LOPD, the levels of GAA enzyme activity and the severity of the clinical pictures may be highly variable among individuals, even in those who harbour the same combination of GAA mutations. The result is an unpredictable genotype–phenotype correlation. The purpose of this study was to identify the genetic factors responsible for the progression, severity and drug response in LOPD. We report here on a detailed clinical, morphological and genetic study, including a whole exome sequencing (WES) analysis of 11 adult LOPD siblings belonging to two Italian families carrying compound heterozygous GAA mutations. We disclosed a heterogeneous pattern of myopathic impairment, associated, among others, with cardiac defects, intracranial vessels abnormality, osteoporosis, vitamin D deficiency, obesity and adverse response to enzyme replacement therapy (ERT). We identified deleterious variants in the genes involved in autophagy, immunity and bone metabolism, which contributed to the severity of the clinical symptoms observed in the LOPD patients. This study emphasizes the multisystem nature of LOPD and highlights the polygenic nature of the complex phenotype disclosed in these patients.

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GW28-e1209 Whole Exome Sequencing Identified a Pathogenic Mutation in RYR2 in a Chinese Family with Unexplained Sudden Death

Journal of the American College of Cardiology ◽

10.1016/j.jacc.2017.07.166 ◽

2017 ◽

Vol 70 (16) ◽

pp. C49

Author(s):

Yubi Lin ◽

Zili Liao ◽

Siqi He ◽

Ruilin Liu ◽

Yongzheng Peng ◽

...

Keyword(s):

Sudden Death ◽

Exome Sequencing ◽

Whole Exome Sequencing ◽

Pathogenic Mutation ◽

Chinese Family ◽

Whole Exome

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Splicing mutants and their second-site suppressors at the dihydrofolate reductase locus in Chinese hamster ovary cells

Molecular and Cellular Biology ◽

10.1128/mcb.13.8.5085-5098.1993 ◽

1993 ◽

Vol 13 (8) ◽

pp. 5085-5098

Author(s):

A M Carothers ◽

G Urlaub ◽

D Grunberger ◽

L A Chasin

Keyword(s):

Dihydrofolate Reductase ◽

Chinese Hamster Ovary ◽

Chinese Hamster Ovary Cells ◽

Consensus Sequence ◽

Donor Site ◽

Chinese Hamster ◽

Base Substitution ◽

Acceptor Site ◽

Rnase Protection ◽

Single Base

Point mutants induced with a variety of mutagens at the dihydrofolate reductase (dhfr) locus in Chinese hamster ovary (CHO) cells were screened for aberrantly spliced dhfr mRNA by RNase protection and/or reverse transcriptase coupled with cDNA amplification by the polymerase chain reaction (PCR). Of 115 mutants screened, 28 were found to be affected in splicing. All exhibited less than 1% correct splicing, probably because the selection procedure was stringent. All 26 unique mutations were located within the consensus splice sequences; changes were found at 9 of 10 possible sites in this 25-kb six-exon gene. Mutations at the sites flanking the first and last exons resulted in the efficient recruitment of a cryptic site within each exon. In contrast, mutations bordering internal exons caused predominantly exon skipping. In many cases, multiple exons were skipped, suggesting the clustering of adjacent exons prior to actual splicing. Six mutations fell outside the well-conserved GU and AG dinucleotides. All but one were donor site single-base substitutions that decreased the agreement with the consensus and resulted in little or no correct splicing. Starting with five of these donor site mutants, we isolated 31 DHFR+ revertants. Most revertants carried a single-base substitution at a site other than that of the original mutation, and most had only partially regained the ability to splice correctly. The second-site suppression occurred through a variety of mechanisms: (i) a second change within the consensus sequence that produced a better agreement with the consensus; (ii) a change close to but beyond the consensus boundaries, as far as 8 bases upstream in the exon or 28 bases downstream in the intron; (iii) mutations in an apparent pseudo 5' site in the intron, 84 and 88 bases downstream of a donor site; and (iv) mutations that improved the upstream acceptor site of the affected exon. Taken together, these second-site suppressor mutations extend the definition of a splice site beyond the consensus sequence.

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