scholarly journals Identification of Novel ARSA Mutations in Chinese Patients with Metachromatic Leukodystrophy

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Li Chen ◽  
Huifang Yan ◽  
Binbin Cao ◽  
Ye Wu ◽  
Qiang Gu ◽  
...  

Objective. Metachromatic leukodystrophy (MLD) is an inherited disease caused by a deficiency of the enzyme arylsulfatase A (ARSA) that leads to severe physiologic and developmental problems. Our study is aimed at elucidating the clinical and genetic characteristics of Chinese MLD patients. Methods. Clinical data of 21 MLD patients was collected. All coding exons of ARSA and their flanking intronic sequences were amplified by polymerase chain reaction and subjected to direct sequencing. Results. All 21 patients were diagnosed with MLD clinically and genetically, out of which 17 patients were late infantile and 4 were juvenile types. A total of 34 ARSA mutations, including 28 novel mutations (22 missense, 1 splicing, 1 nonsense, 3 small insertions, and 1 small deletion mutation) and 6 known mutations (5 missense and 1 small insertion mutation), were identified. Prenatal diagnosis was performed for four pedigrees. One fetus was a patient, two fetuses were carriers, and two were wild type. Conclusions. The present study discovered 28 novel ARSA mutations and widely expanded the mutation spectrum of ARSA. Four successful prenatal diagnoses provided critical information for MLD families.

2019 ◽  
Vol 32 (11) ◽  
pp. 1207-1215
Author(s):  
Babak Emamalizadeh ◽  
Yousef Daneshmandpour ◽  
Abbas Tafakhori ◽  
Sakineh Ranji-Burachaloo ◽  
Sajad Shafiee ◽  
...  

Abstract Background X-linked adrenoleukodystrophy (X-ALD), the most common peroxisomal disorder, is caused by mutations in the ABCD1 gene located on Xq28. X-ALD is characterized by a spectrum of different manifestations varying in patients and families. Methods Four pedigrees with X-ALD consisting of patients and healthy members were selected for investigation of ABCD1 gene mutations. The mutation analysis was performed by polymerase chain reaction (PCR) followed by direct sequencing of all exons. The identified mutations were investigated using bioinformatics tools to predict their effects on the protein product and also to compare the mutated sequence with close species. Results One previously known missense mutation (c.1978 C > T) and three novel mutations (c.1797dupT, c.879delC, c.1218 C > G) were identified in the ABCD1 gene, each in one family. Predicting the effects of the mutations on protein structure and function indicated the probable damaging effect for them with significant alterations in the protein structure. We found three novel mutations in the ABCD1 gene with damaging effects on its protein product and responsible for X-ALD.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 5261-5261
Author(s):  
Jun Xia ◽  
Yunfeng Shen ◽  
Jianyong Li

Abstract Most studies have shown that JAK2V617F was found in nearly all the patients with polycythemia vera (PV) and half of patients with essential thrombocythemia (ET) and idiopathic myelofibrosis (IMF). However, JAK2 exon 12 mutations in JAK2V61F-negetive PV patiens and MPLW515L/K mutations in IMF patiens implied other pathogenesis in these myeloproliferative disorders (MPD). Two parts were included in our research to investigate the JAK2 and c-MPL mutations of MPD patients. Firstly, to evaluate the JAK2 exon 12 mutations and its clinical significance in patients with PV, polymerase chain reaction was used to amply the region of JAK2 exon 12 and direct sequencing was performed to detect mutations of JAK2 exon 12. Clinical features of the PV patients with JAK2 exon 12 mutations and JAK2V617F mutation were retrospectively reviewed. The results showed that the JAK2 exon 12 mutations were detected in 3 of 12 JAK2V617F-negtive PV patients (25.0%). Three JAK2 exon 12 mutations were H538QK539L, K539L and N542-E543del respectively. The patients carrying the mutations of JAK2 exon 12 displayed higher hemoglobin(223.6±15.0 vs190.3±20.2g/l, P<0.05), lower white blood cell counts (7.8±2.3 vs16.2±6.7 *109/l, P<0.05)compared with JAK2V617F-positive PV patients (n=31). Secondly, allele specific polymerase chain reaction (AS-PCR) and gene sequencing were used to detected JAK2V617F, MPLW515L and four types of JAK2 exon 12 mutations (F537-K539delinsL, H538QK539L, K539L, N542-E543del) in 30 IMF patients. Results showed that 15 of 30 (50.0%) patients had JAK2V617F mutation and 2 of 30 (6.7%) patients had MPLW515L mutation. JAK2 exon 12 mutations were not detected in IMF patients. Literature reviews show that this is the first report of JAK2 and c-MPL mutations in a number of Chinese patients with BCR/ABL-negative MPD. It is concluded that the JAK2 exon 12 mutations exist in PV patient and the patients with JAK2 exon 12 mutations are characterized by isolated erythrocytosis. The frequency of MPLW515L mutations is high in IMF, which supports recent studies.


2004 ◽  
Vol 50 (1) ◽  
pp. 93-100 ◽  
Author(s):  
Mercè Garcia-Barceló ◽  
Mai-Har Sham ◽  
Wing-Shan Lee ◽  
Vincent Chi-Hang Lui ◽  
Benedict Ling-Sze Chen ◽  
...  

Abstract Background: Hirschsprung disease (HSCR) is a congenital disorder characterized by an absence of ganglion cells in the nerve plexuses of the lower digestive tract. HSCR has a complex pattern of inheritance and is sometimes associated with mutations in genes of the receptor tyrosine kinase (RET) and endothelin receptor B (EDNRB) signaling pathways, which are crucial for development of the enteric nervous system. Methods: Using PCR amplification and direct sequencing, we screened for mutations and polymorphisms in the coding regions and intron/exon boundaries of the RET, GDNF, EDNRB, and EDN3 genes of 84 HSCR patients and 96 ethnically matched controls. Results: We identified 10 novel and 2 previously described mutations in RET, and 4 and 2 novel mutations in EDNRB and in EDN3, respectively. Potential disease-causing mutations were detected in 24% of the patients. The overall mutation rate was 41% in females and 19% in males (P = 0.06). RET mutations occurred in 19% of the patients. R114H in RET was the most prevalent mutation, representing 7% of the patients or 37% of the patients with RET mutations. To date, such a high frequency of a single mutation has never been reported in unrelated HSCR patients. Mutations in EDNRB, EDN3, and GDNF were found in four, two, and none of the patients, respectively. Two patients with mutations in genes of the EDNRB pathway also harbored a mutation in RET. Three novel and three reported polymorphisms were found in EDNRB, EDN3, and GDNF. Conclusion: This study identifies additional HSCR disease-causing mutations, some peculiar to the Chinese population, and represents the first comprehensive genetic analysis of sporadic HSCR disease in Chinese.


2017 ◽  
Vol 177 (4) ◽  
pp. 389-398 ◽  
Author(s):  
Min Nie ◽  
Hongli Xu ◽  
Rongrong Chen ◽  
Jiangfeng Mao ◽  
Xi Wang ◽  
...  

Objective To analyze ANOS1 gene mutations in a large Chinese Kallmann syndrome (KS) cohort and to characterize the clinical presentation of the disease in patients with ANOS1 mutations. Patients and methods Chinese patients with KS, including 187 sporadic and 23 pedigree cases were recruited. Patients’ ANOS1 gene sequences were analyzed by direct sequencing of PCR-amplified products. In silico analysis was used to assess functional relevance of newly identified missense mutations. Patients’ clinical characteristics were analyzed retrospectively. Result(s) Fifteen nonsynonymous rare ANOS1 variants were found in 13 out of 187 sporadic and 8 out of 23 familial IHH probands. Seven novel (C86F, C90Y, C151W, Y379X, c.1062 + 1G > A, Y579L fs 591X, R597X) and eight recurrent ANOS1 mutations (S38X, R257X, R262X, R423X, R424X, V560I, c.1843-1G > A, p.R631X) were identified. All the novel mutations were predicted to be pathogenic. The prevalence of cryptorchidism was high (38.1%) and occurred in patients with different kind of ANOS1 mutations, while the patients with the same mutation did not present with cryptorchidism uniformly. Conclusion(s) The prevalence of ANOS1 gene mutations is low in sporadic KS patients, but is much higher in familial KS patients. In the present study, we identify seven novel ANOS1 mutations, including two mutations in the CR domain, which are probably pathogenic. These mutations expand the ANOS1 mutation spectrum and provide a foundation for prenatal diagnosis and genetic counseling.


2020 ◽  
Author(s):  
Chong Chen ◽  
Qiao Sun ◽  
Mingmin Gu ◽  
Tianwei Qian ◽  
Dawei Luo ◽  
...  

Abstract Background To determine the clinical characteristics and molecular genetic background responsible for USH2A mutations associated with nonsyndromic retinitis pigmentosa (RP) in five Chinese families, a retrospective cross-sectional study was performed. Data of detailed history and comprehensive ophthalmological examinations were extracted from medical charts. Genomic DNA was sequenced by whole-exome sequencing. The pathogenicity predictions were evaluated by in silico analysis. The structural modeling of the wide-type and mutant USH2A proteins was displayed based on I-Tasser software.Results The ultrawide-field fundus imaging showed a distinctive pattern of hyperautofluorescence in the parafoveal ring with macular sparing. Ten USH2A variants were detected, including seven missense mutations, two splicing mutations and one insertion mutation. Six of these variants have already been reported, and the remaining four were novel. Of the de novo mutations, the p.C931Y and p.G4489S mutations were predicted to be deleterious or probably damaging; the p.M4853V mutation was predicted to be neutral or benign; and the IVS22+3A>G mutation was a splicing mutation that could influence mRNA splicing and affect the formation of the hairpin structure of the USH2A protein.Conclusions Our data further confirm that USH2A plays a pivotal role in the maintenance of photoreceptors and expand the spectrum of USH2A mutations that are associated with nonsyndromic RP in Chinese patients.


2002 ◽  
Vol 128 (2) ◽  
pp. 337-342 ◽  
Author(s):  
T. ENDOH ◽  
A. YAGIHASHI ◽  
N. UEHARA ◽  
D. KOBAYASHI ◽  
N. TSUJI ◽  
...  

Thirty Japanese clinical isolates of Mycobacterium tuberculosis were analysed by pyrazinamide susceptibility testing and pyrazinamidase assay, as well as polymerase chain reaction for single-strand conformational polymorphism and direct sequencing of the gene encoding pyrazinamidase (pncA). All sensitive isolates showed pyrazinamidase activity and a wild-type pncA gene, but three resistant isolates had pncA gene mutations and lacked pyrazinamidase activity. The latter isolates showed a minimum inhibitory concentration of at least 100 mg/l by the 7H10 agar proportion method and 400 mg/l by the 7H9 liquid medium method. Isolate 28 showed T-to-C change at position 11, leading to Leu4→Ser substitution; isolate 29 had an 8-bp deletion from position 382; and isolate 30 had A-to-C change at position 29, leading to Gln10→Pro substitution. The deletion has not been described previously. This is the first demonstration of pncA gene mutations in PZA-resistant M. tuberculosis strains isolated from Japanese patients.


Blood ◽  
2001 ◽  
Vol 98 (8) ◽  
pp. 2584-2587 ◽  
Author(s):  
Anskar Y. H. Leung ◽  
Howard C. H. Chow ◽  
Y. L. Kwong ◽  
Albert K. W. Lie ◽  
Alvin T. K. Fung ◽  
...  

Abstract CYP2C9 polymorphisms reported in Caucasians (Arg144Cys in exon 3 and Ile359Leu in exon 7) are extremely uncommon in Chinese persons. The genotype of CYP2C9 in this population was characterized to investigate its relation with the interindividual variation in warfarin dosages. Eighty-nine Chinese patients receiving warfarin were recruited. Target sequences inCYP2C9 in exons 1, 4, and 5 were amplified by polymerase chain reaction, followed by direct sequencing. Polymorphisms at 4 positions were demonstrated in exon 4. Heterozygosities for 608TTG>GTG (Leu208Val), 561CAG>CCG (Gln192Pro), 537CAT>CCT (His184Pro), and 527ATT>CTT (Ile181Leu) existed at frequencies 0.75, 0.20, 0.10, and 0.09, respectively. Seventeen patients (frequency, 0.19) were homozygous for Val208. The common genotypic combinations at these loci are Ile181/His184/Gln192/Leu208Val (n = 50), Ile181/His184/Gln192/Val208 (n = 15), Ile181/His184/Gln192/Leu208 (n = 4), Ile181/His184/Gln192Pro/Leu208Val (n = 6), Ile181/His184Pro/Gln192Pro/Leu208Val (n = 4), and Ile181Leu/His184/Gln192Pro/ Leu208Val (n = 4). At codon 208, heterozygous Leu208Val and homozygous Val208 appeared to have a lower warfarin dose requirement than the homozygous Leu208. Patients who are heterozygous for Ile181Leu had a higher warfarin dose requirement than the homozygous Ile181. Amplified sequences in exons 1 and 5 did not exhibit polymorphism. In conclusion, Chinese patients showed genetic polymorphisms of CYP2C9 in exon 4 and at codon 208; most were heterozygous Leu208Val and homozygous Val208. Homozygous Leu208, a common allele in Caucasians, is uncommon in this cohort. The significance of these CYP2C9 polymorphic alleles remains to be determined.


2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
Bo-Da Wu ◽  
Yong-Jun Wang ◽  
Liang-Liang Fan ◽  
Hui Huang ◽  
Peng Zhou ◽  
...  

Background. Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant inherited disease caused by a germline mutation in the STK11 gene. It is characterized by mucocutaneous pigmentation, gastrointestinal hamartomatous polyps, and cancer predisposition. Aims. We aimed to summarize the main clinical and genetic features of Chinese PJS patients and assessed the genotype-phenotype correlations. Methods. Thirty-eight patients clinically diagnosed with Peutz-Jeghers syndrome were included in this study from 2016 to 2019. Combined direct sequencing and multiplex ligation-dependent probe amplification tests were used to detect germline heterogeneous STK11 mutations. RNA sequencing was performed in polyps of PJS patients and control groups to evaluate the difference in expression of STK11. The genotype-phenotype correlations were calculated by Kaplan-Meier analyses. Results. All 26 probands and 12 affected relatives had germline heterogeneous STK11 mutations among which 8 variants were novel. Individuals with missense mutations had their first surgery and other symptoms significantly later than individuals with null mutations. Conclusion. This study expanded the spectrum of STK11 gene mutations and further elucidated individuals with null mutations of STK11 typically had an earlier onset of PJS symptoms and needed earlier management.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Safia Akhtar ◽  
Silas A. Culver ◽  
Helmy M. Siragy

AbstractRecent studies suggested that renal gluconeogenesis is substantially stimulated in the kidney in presence of obesity. However, the mechanisms responsible for such stimulation are not well understood. Recently, our laboratory demonstrated that mice fed high fat diet (HFD) exhibited increase in renal Atp6ap2 [also known as (Pro)renin receptor] expression. We hypothesized that HFD upregulates renal gluconeogenesis via Atp6ap2-PGC-1α and AKT pathway. Using real-time polymerase chain reaction, western blot analysis and immunostaining, we evaluated renal expression of the Atp6ap2 and renal gluconeogenic enzymes, PEPCK and G6Pase, in wild type and inducible nephron specific Atp6ap2 knockout mice fed normal diet (ND, 12 kcal% fat) or a high-fat diet (HFD, 45 kcal% fat) for 8 weeks. Compared with ND, HFD mice had significantly higher body weight (23%) (P < 0.05), renal mRNA and protein expression of Atp6ap2 (39 and 35%), PEPCK (44 and 125%) and G6Pase (39 and 44%) respectively. In addition, compared to ND, HFD mice had increased renal protein expression of PGC-1α by 32% (P < 0.05) and downregulated AKT by 33% (P < 0.05) respectively in renal cortex. Atp6ap2-KO abrogated these changes in the mice fed HFD. In conclusion, we identified novel regulation of renal gluconeogenesis by Atp6ap2 in response to high fat diet via PGC1-α/AKT-1 pathway.


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