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Qiu X, Zhao P, Luo J, Li G, Deng L, Zeng Y, Xu L, Zhou J. Biochemical and molecular features of tetrahydrobiopterin deficiency in Fujian Province, southeastern China. Front Genet 2023; 14:1250568. [PMID: 37636258 PMCID: PMC10451069 DOI: 10.3389/fgene.2023.1250568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 08/04/2023] [Indexed: 08/29/2023] Open
Abstract
The estimated prevalence of tetrahydrobiopterin deficiency (BH4D) and the mutational spectrum of the causal 6-pyruvoyl-tetrahydropterin synthase (PTS) gene vary widely according to race and region. This study assessed the prevalence and genetic characteristics of BH4D in Fujian Province, southeastern China. A total of 3,204,067 newborns were screened between 2012 and 2022 based on the phenylalanine level and the phenylalanine/tyrosine ratio in dried blood spots. Differential diagnosis was determined by the urine purine spectrum, dihydropteridine reductase activity in red blood cells, and genetic testing. The PTS mutation spectrum and genotypes were determined by next-generation sequencing. A total of 189 newborns were diagnosed with hyperphenylalaninemia (HPA) over the study period, including 159 with phenylalanine hydroxylase deficiency and 30 with BH4D. Therefore, the prevalence of BH4D in Fujian was 9.36 per 1,000,000 live births (30/3,204,067) and the proportion of BH4D among patients with HPA was 15.87% (30/189). A total of 58 PTS alleles were identified in the 29 patients with PTS deficiency (PTPSD), and those alleles were composed of 10 different variants, including eight missense variants and two splice-site variants. The most prevalent variants were c.155A>G, p.Asn52Ser (44.83%); c.259C>T, p.Pro87Ser (39.66%); and c.84-291A>G, p.Tyr27Argfs*8 (3.45%). The predominant genotype was c [155A>G]; [259C>T] (11/29, 37.93%). The prevalence of BH4D and the spectrum of associated PTS mutations were successfully determined for the first time in Fujian Province, southeastern China. Since the mutation spectrum of PTS is region-specific, such data will facilitate molecular diagnosis and genetic counseling in PTPSD cases.
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Affiliation(s)
- Xiaolong Qiu
- Genetic Diagnosis and Therapy Center, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fujian Maternity and Child Hospital, College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, China
| | - Peiran Zhao
- Genetic Diagnosis and Therapy Center, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fujian Maternity and Child Hospital, College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, China
| | - Jinying Luo
- Obstetrics and Gynecology Department, Fujian Maternity and Child Hospital, College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, China
| | - Guilin Li
- Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou, China
| | - Lin Deng
- Obstetrics and Gynecology Department, Fujian Maternity and Child Hospital, College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, China
| | - Yinglin Zeng
- Genetic Diagnosis and Therapy Center, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fujian Maternity and Child Hospital, College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, China
| | - Liangpu Xu
- Genetic Diagnosis and Therapy Center, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fujian Maternity and Child Hospital, College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, China
| | - Jinfu Zhou
- Genetic Diagnosis and Therapy Center, Fujian Key Laboratory for Prenatal Diagnosis and Birth Defect, Fujian Maternity and Child Hospital, College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, China
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Xie K, Zeng B, Zhang L, Chen S, Zou Y, Yuan H, Huang S, Wang F, Lu Q, Liu Y, Yang B. Mutation spectrum of PTS gene in patients with tetrahydrobiopterin deficiency from jiangxi province. Front Genet 2022; 13:1077729. [PMID: 36583021 PMCID: PMC9792861 DOI: 10.3389/fgene.2022.1077729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 11/29/2022] [Indexed: 12/15/2022] Open
Abstract
Background: Hyperphenylalaninemia (HPA) is the most common inborn error in amino acid metabolism. It can be primarily classified into phenylalanine hydroxylase (PAH) deficiency and tetrahydrobiopterin (BH4) deficiency. BH4 deficiency (BH4D) is caused by genetic defects in enzymes involved in the biosynthesis and regeneration of BH4. 6-pyruvoyl-tetrahydropterin synthase (PTPS/PTS), which is encoded by the PTS gene, participates in the biosynthesis of BH4. PTPS deficiency (PTPSD) is the major cause of BH4D. In this study, we investigated that the prevalence of BH4D in Jiangxi province was approximately 12.5 per 1,000,000 live births (69/5,541,627). Furthermore, the frequency of BH4D was estimated to be 28.8% (69/240) in the HPA population of Jiangxi. In this study, we aimed to characterize the mutational spectrum of the PTS gene in patients with PTPSD from Jiangxi province. Method: Newborn screening data of Jiangxi province from 1997 to 2021 were analyzed and 53 families with PTPSD were enrolled for the analysis of the PTS gene variants by Sanger sequencing. Results: 106 variants were identified in 106 alleles of 53 patients with PTPSD, including 13 types of variants reported previously, and two novel variants (c.164-36A>G and c.146_147insTG). The predominant variant was c.259C>T (47.2%), followed by c.84-291A>G (19.8%), c.155A>G (8.5%), c.286G>A (6.6%) and c.379C>T (4.7%). Conclusion: The results of this study can not only provide guidance for the molecular diagnosis and genetic counseling in cases of PTPS deficiency but also enrich the PTS mutation database.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Qing Lu
- *Correspondence: Qing Lu, ; Yanqiu Liu, ; Bicheng Yang,
| | - Yanqiu Liu
- *Correspondence: Qing Lu, ; Yanqiu Liu, ; Bicheng Yang,
| | - Bicheng Yang
- *Correspondence: Qing Lu, ; Yanqiu Liu, ; Bicheng Yang,
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Hertzog A, Selvanathan A, Farnsworth E, Tchan M, Adams L, Lewis K, Tolun AA, Bennetts B, Ho G, Bhattacharya K. Intronic variants in inborn errors of metabolism: Beyond the exome. Front Genet 2022; 13:1031495. [PMID: 36561316 PMCID: PMC9763607 DOI: 10.3389/fgene.2022.1031495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 11/15/2022] [Indexed: 12/12/2022] Open
Abstract
Non-coding regions are areas of the genome that do not directly encode protein and were initially thought to be of little biological relevance. However, subsequent identification of pathogenic variants in these regions indicates there are exceptions to this assertion. With the increasing availability of next generation sequencing, variants in non-coding regions are often considered when no causative exonic changes have been identified. There is still a lack of understanding of normal human variation in non-coding areas. As a result, potentially pathogenic non-coding variants are initially classified as variants of uncertain significance or are even overlooked during genomic analysis. In most cases where the phenotype is non-specific, clinical suspicion is not sufficient to warrant further exploration of these changes, partly due to the magnitude of non-coding variants identified. In contrast, inborn errors of metabolism (IEMs) are one group of genetic disorders where there is often high phenotypic specificity. The clinical and biochemical features seen often result in a narrow list of diagnostic possibilities. In this context, there have been numerous cases in which suspicion of a particular IEM led to the discovery of a variant in a non-coding region. We present four patients with IEMs where the molecular aetiology was identified within non-coding regions. Confirmation of the molecular diagnosis is often aided by the clinical and biochemical specificity associated with IEMs. Whilst the clinical severity associated with a non-coding variant can be difficult to predict, obtaining a molecular diagnosis is crucial as it ends diagnostic odysseys and assists in management.
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Affiliation(s)
- Ashley Hertzog
- NSW Biochemical Genetics Service, Western Sydney Genetics Program, The Children’s Hospital at Westmead, Sydney, NSW, Australia,Disciplines of Genetic Medicine and Child and Adolescent Health, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia,*Correspondence: Ashley Hertzog,
| | - Arthavan Selvanathan
- Genetic Metabolic Disorders Service, Sydney Children’s Hospitals Network, Sydney, NSW, Australia
| | - Elizabeth Farnsworth
- Department of Molecular Genetics, Sydney Genome Diagnostics, Western Sydney Genetics Program, The Children’s Hospital at Westmead, Sydney, NSW, Australia
| | - Michel Tchan
- Department of Genetic Medicine, Westmead Hospital, Sydney, NSW, Australia
| | - Louisa Adams
- Genetic Metabolic Disorders Service, Sydney Children’s Hospitals Network, Sydney, NSW, Australia
| | - Katherine Lewis
- Genetic Metabolic Disorders Service, Sydney Children’s Hospitals Network, Sydney, NSW, Australia
| | - Adviye Ayper Tolun
- NSW Biochemical Genetics Service, Western Sydney Genetics Program, The Children’s Hospital at Westmead, Sydney, NSW, Australia,Disciplines of Genetic Medicine and Child and Adolescent Health, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Bruce Bennetts
- Disciplines of Genetic Medicine and Child and Adolescent Health, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia,Department of Molecular Genetics, Sydney Genome Diagnostics, Western Sydney Genetics Program, The Children’s Hospital at Westmead, Sydney, NSW, Australia
| | - Gladys Ho
- Disciplines of Genetic Medicine and Child and Adolescent Health, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia,Department of Molecular Genetics, Sydney Genome Diagnostics, Western Sydney Genetics Program, The Children’s Hospital at Westmead, Sydney, NSW, Australia
| | - Kaustuv Bhattacharya
- Disciplines of Genetic Medicine and Child and Adolescent Health, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia,Genetic Metabolic Disorders Service, Sydney Children’s Hospitals Network, Sydney, NSW, Australia
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Sadat Fatemi SH, Eshraghi P, Ghanei M, Hamzehloei T. Genetic evaluation of hyperphenylalaninemia patients with tetrahydrobiopterin deficiency in Iranian population: Identification of four novel disease-causing variants. Mol Genet Genomic Med 2022; 10:e2081. [PMID: 36382472 DOI: 10.1002/mgg3.2081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 10/09/2022] [Accepted: 10/21/2022] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Hyperphenylalaninemia (HPA) is the most common inborn error of amino acid metabolism worldwide. At least 2% of HPA cases are caused by a deficiency in tetrahydrobiopterin (BH4) metabolism. Genes such as QDPR and PTS are essential in the BH4 metabolism. This study aims to identify disease-causing variants in HPA patients, which may be helpful in genetic counseling and prenatal diagnosis. METHODS A total of 10 HPA patients were enrolled in this study. The coding and adjacent intronic regions of PTS and QDPR genes were examined using Sanger sequencing. Protein modeling was also performed for novel identified variants. RESULTS Ten patients and a total of 20 alleles were studied, which led to the identification of 10 different variants. All variants identified in PTS and QDPR were missense, except for the c.383_407del variant in the QDPR. Also, three novel variants were identified in the QDPR, including c.79G>T, c.383_407del and c.488G>A, and a novel variant, c.65C>G, in the PTS. CONCLUSIONS Despite the genetic similarities in the disease-causing variants, differences were observed in the Asian and European populations with our populations; As a result, similar but more extensive studies are needed to investigate the distribution of disease-causing variants in genes involved in non-PKU hyperphenylalaninemia.
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Affiliation(s)
- Seyedeh Helia Sadat Fatemi
- Medical Genetics and Molecular Medicine Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Medical Genetics Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Peyman Eshraghi
- Clinical Research Development Unit of Akbar Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mahmoud Ghanei
- Medical Genetics and Molecular Medicine Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.,Medical Genetics Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Tayebeh Hamzehloei
- Medical Genetics and Molecular Medicine Department, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
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Vela-Amieva M, Alcántara-Ortigoza MA, Ibarra-González I, González-del Angel A, Fernández-Hernández L, Guillén-López S, López-Mejía L, Carrillo-Nieto RI, Fiesco-Roa MO, Fernández-Lainez C. Genotypic spectrum underlying tetrahydrobiopterin metabolism defects: Experience in a single Mexican reference center. Front Genet 2022; 13:993612. [PMID: 36313470 PMCID: PMC9597361 DOI: 10.3389/fgene.2022.993612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/30/2022] [Indexed: 11/29/2022] Open
Abstract
Background: Pterin profiles or molecular analyses of hyperphenylalaninemia (HPA) caused by phenylalanine hydroxylase (PAH) deficiency or tetrahydrobiopterin deficiency (BH4D) are not always available in low- or middle-income countries, including Mexico, limiting information regarding the phenotypic and genotypic characteristics of patients exhibiting BH4D. Objective: To report the genotypes underlying BH4D and the clinical presentation in unrelated Mexican HPA pediatric patients with normal PAH genotypes who attended a single metabolic reference center in Mexico. Methods: Automated Sanger sequencing of the PTS, QDPR, and PCBD1 genes of 14 HPA patients was performed. Predicted effects on protein structure caused by missense variants were assessed by in silico protein modeling. Results and discussion: A high prevalence of BH4D was noted in our HPA cohort (9.8%, N = 14/142). Clinically relevant biallelic genotypes were identified in the PTS (N = 7/14 patients), QDPR (N = 6/14 patients), and PCBD1 (N = 1/14 patients) genes. Four novel QDPR variants [c.714dup or p.(Leu239Thrfs*44), c.106-1G>T or p.(?), c.214G>T or p.(Gly72*), and c.187_189dup or p.(Gln63dup)] were identified. In silico protein modeling of six missense variants of PTS [p.(Thr67Met), p.(Glu81Ala), and p.(Tyr113Cys)], QDPR [p.(Cys161Phe) and p.(Pro172Leu)], and PCBD1 [p.(Glu97Lys)] supports their pathogenicity. Progressive neurological symptoms (mainly intellectual and motor impairment and even death in three patients) were noted in all patients with biallelic QDPR genotypes and in 5/7 patients bearing biallelic PTS genotypes. The single homozygous PCBD1 p.(Glu97Lys) patient remains asymptomatic. Conclusion: A higher proportion of BH4D (9.8 vs. 1%–2% worldwide), attributable to a heterogeneous mutational spectrum and wide clinical presentation, was noted in our Mexican HPA cohort, with the PTS-related HPA disorder being the most frequent. Sequencing-based assays could be a reliable approach for diagnosing BH4D in our population.
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Affiliation(s)
- M. Vela-Amieva
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, México
| | - M. A. Alcántara-Ortigoza
- Laboratorio de Biología Molecular, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, México
| | - I. Ibarra-González
- Unidad de Genética de la Nutrición, Instituto de Investigaciones Biomédicas, UNAM, Ciudad de México, México
| | - A. González-del Angel
- Laboratorio de Biología Molecular, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, México
| | - L. Fernández-Hernández
- Laboratorio de Biología Molecular, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, México
| | - S. Guillén-López
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, México
| | - L. López-Mejía
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, México
| | - R. I. Carrillo-Nieto
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, México
| | - M. O. Fiesco-Roa
- Laboratorio de Citogenética, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, México
- Maestría y Doctorado en Ciencias Médicas y de la Salud, UNAM, Ciudad de México, México
| | - C. Fernández-Lainez
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaría de Salud, Ciudad de México, México
- *Correspondence: C. Fernández-Lainez,
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Khamooshian S, Kazeminia M, Moradi K. In silico analysis and the pathogenicity classification of PTS gene variants among Iranian population. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2022. [DOI: 10.1186/s43042-022-00351-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
6-Pyruvoyl-tetrahydropterin synthase (PTPS) deficiency is an autosomal recessive disorder caused by PTS gene mutations. The aim of this study was to collect all PTS gene variants detected among Iranian patients with PTPS deficiency as well as in the Iranome project and classify them based on American College of Medical Genetics and Genomics (ACMG-AMP) guidelines.
Results
The number of PTS gene variants reported among Iranian PTPS patients and in the Iranome project were 19 and 36, respectively. Given that one variant was reported in both of our sources, the total number of variants was 54. These variants were classified as pathogenic (n = 11), likely pathogenic (n = 7), VUS (n = 23), likely benign (n = 1), and benign (n = 12). Out of 19 variants reported among Iranian PTPS patients, c.155A>G (p.Asn52Ser, rs104894275) and c.317C>T (p.Thr106Met, rs200712908) were the most frequent ones, each with a frequency of 10%. c.84-3C>G (rs1230781262) (7.5%) and c.281A>T (p.Asp94Val) (5%) were in the next ranks of the list of variants.
Conclusions
The ACMG-AMP criteria need to be updated depending on the type of disease. In addition, to the best of our knowledge, no template has been described for classifying the variants identified in PTPS deficiency. Therefore, this study can be a good reference for future studies in this subject.
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Li L, Yang H, Zhao J, Yang N, Gong L, Tang Y, Kong Y. Identification and molecular analysis of 11 cases of the PTS gene variants associated with tetrahydrobiopterin deficiency. Front Genet 2022; 13:919209. [PMID: 36212127 PMCID: PMC9536429 DOI: 10.3389/fgene.2022.919209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 07/07/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Tetrahydrobiopterin deficiency (BH4D) is a rare autosomal recessive amino acid metabolic disease that belongs to a kind of hyperphenylalaninemia (HPA), and 6-pyruvyltetrahydrotrexate synthase (PTPS) deficiency is the most common type of BH4D. This study investigates the clinical and genetic characteristics of 11 PTPS deficiency cases in the Beijing area, identifies the genetic pathogenic factors, and evaluates the value of high-throughput sequencing in the precise diagnosis of PTPS deficiency.Methods: The Beijing Neonatal Disease Screening Center diagnosed patients with HPA. The study used phenylalanine (Phe) in blood, the ratio of Phe to Thr, urotrexate spectrum analysis, erythrocyte dihydrotrexate reductase (DHPR) activity determination, and high-throughput sequencing as methods. Bioinformatics software analyzed the variants’ pathogenicity and used RT-PCR to identify deep intron variants’ pathogenicity.Result: Among 635 cases with HPA, 38 cases were diagnosed with BH4D, of which the incidence in HPA was 5.98%. Nine kinds of PTS gene variants were detected, including seven missense variants, one splicing variant, and one deletion variant. The splicing variant c.84–291A>G had three splicing results in vivo: normal length, 79bp pseudoexon insertion, and exon 3 skipping. Bioinformatics and Sanger sequencing were performed to verify the identified variants.Conclusion: High-throughput sequencing is a helpful tool for clinical diagnosis and differential diagnosis of BH4D. This study confirms that c.84–291A>G is the hot spot variant of PTPS deficiency, and it is the first reported variant with a new splicing pattern in vivo. A novel deletion variant c.84_163del (p.Lys29Cysfs∗9) was found to enrich the genetic variant spectrum of the disease.
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Elhawary NA, AlJahdali IA, Abumansour IS, Elhawary EN, Gaboon N, Dandini M, Madkhali A, Alosaimi W, Alzahrani A, Aljohani F, Melibary EM, Kensara OA. Genetic etiology and clinical challenges of phenylketonuria. Hum Genomics 2022; 16:22. [PMID: 35854334 PMCID: PMC9295449 DOI: 10.1186/s40246-022-00398-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 07/08/2022] [Indexed: 02/08/2023] Open
Abstract
This review discusses the epidemiology, pathophysiology, genetic etiology, and management of phenylketonuria (PKU). PKU, an autosomal recessive disease, is an inborn error of phenylalanine (Phe) metabolism caused by pathogenic variants in the phenylalanine hydroxylase (PAH) gene. The prevalence of PKU varies widely among ethnicities and geographic regions, affecting approximately 1 in 24,000 individuals worldwide. Deficiency in the PAH enzyme or, in rare cases, the cofactor tetrahydrobiopterin results in high blood Phe concentrations, causing brain dysfunction. Untreated PKU, also known as PAH deficiency, results in severe and irreversible intellectual disability, epilepsy, behavioral disorders, and clinical features such as acquired microcephaly, seizures, psychological signs, and generalized hypopigmentation of skin (including hair and eyes). Severe phenotypes are classic PKU, and less severe forms of PAH deficiency are moderate PKU, mild PKU, mild hyperphenylalaninaemia (HPA), or benign HPA. Early diagnosis and intervention must start shortly after birth to prevent major cognitive and neurological effects. Dietary treatment, including natural protein restriction and Phe-free supplements, must be used to maintain blood Phe concentrations of 120-360 μmol/L throughout the life span. Additional treatments include the casein glycomacropeptide (GMP), which contains very limited aromatic amino acids and may improve immunological function, and large neutral amino acid (LNAA) supplementation to prevent plasma Phe transport into the brain. The synthetic BH4 analog, sapropterin hydrochloride (i.e., Kuvan®, BioMarin), is another potential treatment that activates residual PAH, thus decreasing Phe concentrations in the blood of PKU patients. Moreover, daily subcutaneous injection of pegylated Phe ammonia-lyase (i.e., pegvaliase; PALYNZIQ®, BioMarin) has promised gene therapy in recent clinical trials, and mRNA approaches are also being studied.
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Affiliation(s)
- Nasser A. Elhawary
- grid.412832.e0000 0000 9137 6644Department of Medical Genetics, College of Medicine, Umm Al-Qura University, P.O. Box 57543, Mecca, 21955 Saudi Arabia
| | - Imad A. AlJahdali
- grid.412832.e0000 0000 9137 6644Department of Community Medicine, College of Medicine, Umm Al-Qura University, P.O. Box 57543, Mecca, 21955 Saudi Arabia
| | - Iman S. Abumansour
- grid.412832.e0000 0000 9137 6644Department of Medical Genetics, College of Medicine, Umm Al-Qura University, P.O. Box 57543, Mecca, 21955 Saudi Arabia
| | - Ezzeldin N. Elhawary
- grid.123047.30000000103590315Faculty of Medicine, MS Genomic Medicine Program, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Nagwa Gaboon
- grid.7269.a0000 0004 0621 1570Department of Clinical Genetics, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Mohammed Dandini
- Department of Laboratory and Blood Bank, Maternity and Children Hospital, Mecca, Saudi Arabia
| | - Abdulelah Madkhali
- grid.415254.30000 0004 1790 7311Department of Pathology and Laboratory Medicine, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - Wafaa Alosaimi
- Department of Hematology, Maternity and Children Hospital, Mecca, Saudi Arabia
| | - Abdulmajeed Alzahrani
- Department of Laboratory and Blood Bank at Maternity and Children Hospital, Mecca, Saudi Arabia
| | - Fawzia Aljohani
- Department of Pediatric Clinics, Maternity and Children Hospital, King Salman Medical City, Madinah, Saudi Arabia
| | - Ehab M. Melibary
- grid.412832.e0000 0000 9137 6644Department of Medical Genetics, College of Medicine, Umm Al-Qura University, P.O. Box 57543, Mecca, 21955 Saudi Arabia
| | - Osama A. Kensara
- grid.412832.e0000 0000 9137 6644Department of Clinical Nutrition, Faculty of Applied Medical Sciences, Umm Al-Qura University, Jeddah, Saudi Arabia
- Department of Biochemistry, Batterjee Medical College, Jeddah, Saudi Arabia
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Keegan NP, Wilton SD, Fletcher S. Analysis of Pathogenic Pseudoexons Reveals Novel Mechanisms Driving Cryptic Splicing. Front Genet 2022; 12:806946. [PMID: 35140743 PMCID: PMC8819188 DOI: 10.3389/fgene.2021.806946] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 12/09/2021] [Indexed: 12/16/2022] Open
Abstract
Understanding pre-mRNA splicing is crucial to accurately diagnosing and treating genetic diseases. However, mutations that alter splicing can exert highly diverse effects. Of all the known types of splicing mutations, perhaps the rarest and most difficult to predict are those that activate pseudoexons, sometimes also called cryptic exons. Unlike other splicing mutations that either destroy or redirect existing splice events, pseudoexon mutations appear to create entirely new exons within introns. Since exon definition in vertebrates requires coordinated arrangements of numerous RNA motifs, one might expect that pseudoexons would only arise when rearrangements of intronic DNA create novel exons by chance. Surprisingly, although such mutations do occur, a far more common cause of pseudoexons is deep-intronic single nucleotide variants, raising the question of why these latent exon-like tracts near the mutation sites have not already been purged from the genome by the evolutionary advantage of more efficient splicing. Possible answers may lie in deep intronic splicing processes such as recursive splicing or poison exon splicing. Because these processes utilize intronic motifs that benignly engage with the spliceosome, the regions involved may be more susceptible to exonization than other intronic regions would be. We speculated that a comprehensive study of reported pseudoexons might detect alignments with known deep intronic splice sites and could also permit the characterisation of novel pseudoexon categories. In this report, we present and analyse a catalogue of over 400 published pseudoexon splice events. In addition to confirming prior observations of the most common pseudoexon mutation types, the size of this catalogue also enabled us to suggest new categories for some of the rarer types of pseudoexon mutation. By comparing our catalogue against published datasets of non-canonical splice events, we also found that 15.7% of pseudoexons exhibit some splicing activity at one or both of their splice sites in non-mutant cells. Importantly, this included seven examples of experimentally confirmed recursive splice sites, confirming for the first time a long-suspected link between these two splicing phenomena. These findings have the potential to improve the fidelity of genetic diagnostics and reveal new targets for splice-modulating therapies.
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Affiliation(s)
- Niall P. Keegan
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, Perron Institute for Neurological and Translational Science, The University of Western Australia, Perth, WA, Australia
- *Correspondence: Niall P. Keegan,
| | - Steve D. Wilton
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, Perron Institute for Neurological and Translational Science, The University of Western Australia, Perth, WA, Australia
| | - Sue Fletcher
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA, Australia
- Centre for Neuromuscular and Neurological Disorders, Perron Institute for Neurological and Translational Science, The University of Western Australia, Perth, WA, Australia
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10
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Song B, Ma Z, Liu W, Lu L, Jian Y, Yu L, Wan Z, Yue X, Kong Y. Clinical, biochemical and molecular spectrum of mild 6-pyruvoyl-tetrahydropterin synthase deficiency and a case report. Fetal Pediatr Pathol 2021; 40:707-716. [PMID: 32202960 DOI: 10.1080/15513815.2020.1737992] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Background 6-Pyruvoyl-tetrahydropterin synthase (PTS) is the key enzyme in BH4 synthesis. PTS deficiency is classified as severe type and mild type, and the prognosis and treatment differ for these types. Distinguishing between two types in the early stage is difficult. Reference to reported cases is needed for interpretation of the correlation between genotype and prognosis. Case report: We report a full-term female newborn with mild PTS deficiency. On the day 21 after birth, the phenylalanine level was 859.6 mmol/L (reference range: 30-117 mmol/L). After 1 year of observation, the patient was found to be in a healthy condition without treatment. Conclusions: Although the phenylalanine level is high in mild PTS deficiency patients after birth, some of them may have few symptoms with no treatment. We review 19 cases and find 8 mutations of PTS that may be associated with mild PTS deficiency.
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Affiliation(s)
- Boyan Song
- Department of Laboratory Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Zhijun Ma
- Department of Laboratory Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Wei Liu
- Department of Laboratory Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Lihong Lu
- Department of Laboratory Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Yongjian Jian
- Department of Laboratory Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Lu Yu
- Department of Laboratory Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Zhihui Wan
- Department of Laboratory Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Xiaofei Yue
- Department of Laboratory Medicine, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Yuanyuan Kong
- Newborn Screening Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
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11
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Pinheiro FC, Sperb-Ludwig F, Schwartz IVD. Epidemiological aspects of hereditary fructose intolerance: A database study. Hum Mutat 2021; 42:1548-1566. [PMID: 34524712 DOI: 10.1002/humu.24282] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 09/05/2021] [Accepted: 09/11/2021] [Indexed: 12/11/2022]
Abstract
Hereditary fructose intolerance (HFI) is an inborn error of fructose metabolism of autosomal recessive inheritance caused by pathogenic variants in the ALDOB gene that lead to aldolase B deficiency in the liver, kidneys, and intestine. Patients manifest symptoms, such as ketotic hypoglycemia, vomiting, nausea, in addition to hepatomegaly and other liver and kidney dysfunctions. The treatment consists of a fructose-restricted diet, which results in a good prognosis. To analyze the distribution of ALDOB variants described in patients and to estimate the prevalence of HFI based on carrier frequency in the gnomAD database, a systematic review was conducted to assess ALDOB gene variants among patients with HFI. The prevalence of HFI was estimated from the carrier frequency of variants described in patients, as well as rare variants predicted as pathogenic by in silico tools. The p.(Ala150Pro) and p.(Ala175Asp) variants are the most frequent and are distributed worldwide. However, these variants have particular distribution patterns in Europe. The analysis of the prevalence of HFI showed that the inclusion of rare alleles predicted as pathogenic is a more informative approach for populations with few patients. The data show that HFI has a wide distribution and an estimated prevalence of ~1:10,000.
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Affiliation(s)
- Franciele C Pinheiro
- Post-Graduate Program in Genetics and Molecular Biology, Federal University of do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,BRAIN Laboratory, Center of Experimental Research, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil.,Federal University of Pampa, Itaqui, Rio Grande do Sul, Brazil
| | - Fernanda Sperb-Ludwig
- Post-Graduate Program in Genetics and Molecular Biology, Federal University of do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,BRAIN Laboratory, Center of Experimental Research, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Ida V D Schwartz
- Post-Graduate Program in Genetics and Molecular Biology, Federal University of do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,BRAIN Laboratory, Center of Experimental Research, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil.,Department of Genetics, Bioscience Institute, Federal University of do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Medical Genetics Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
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12
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Himmelreich N, Blau N, Thöny B. Molecular and metabolic bases of tetrahydrobiopterin (BH 4) deficiencies. Mol Genet Metab 2021; 133:123-136. [PMID: 33903016 DOI: 10.1016/j.ymgme.2021.04.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/09/2021] [Accepted: 04/09/2021] [Indexed: 01/01/2023]
Abstract
Tetrahydrobiopterin (BH4) deficiency is caused by genetic variants in the three genes involved in de novo cofactor biosynthesis, GTP cyclohydrolase I (GTPCH/GCH1), 6-pyruvoyl-tetrahydropterin synthase (PTPS/PTS), sepiapterin reductase (SR/SPR), and the two genes involved in cofactor recycling, carbinolamine-4α-dehydratase (PCD/PCBD1) and dihydropteridine reductase (DHPR/QDPR). Dysfunction in BH4 metabolism leads to reduced cofactor levels and may result in systemic hyperphenylalaninemia and/or neurological sequelae due to secondary deficiency in monoamine neurotransmitters in the central nervous system. More than 1100 patients with BH4 deficiency and 800 different allelic variants distributed throughout the individual genes are tabulated in database of pediatric neurotransmitter disorders PNDdb. Here we provide an update on the molecular-genetic analysis and structural considerations of these variants, including the clinical courses of the genotypes. From a total of 324 alleles, 11 are associated with the autosomal recessive form of GTPCH deficiency presenting with hyperphenylalaninemia (HPA) and neurotransmitter deficiency, 295 GCH1 variant alleles are detected in the dominant form of L-dopa-responsive dystonia (DRD or Segawa disease) while phenotypes of 18 alleles remained undefined. Autosomal recessive variants observed in the PTS (199 variants), PCBD1 (32 variants), and QDPR (141 variants) genes lead to HPA concomitant with central monoamine neurotransmitter deficiency, while SPR deficiency (104 variants) presents without hyperphenylalaninemia. The clinical impact of reported variants is essential for genetic counseling and important for development of precision medicine.
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Affiliation(s)
- Nastassja Himmelreich
- Center for Child and Adolescent Medicine, Dietmar-Hopp Metabolic Center, Division 1, Heidelberg, Germany
| | - Nenad Blau
- Division of Metabolism, University Children's Hospital Zürich, Zürich, Switzerland.
| | - Beat Thöny
- Division of Metabolism and Children's Research Centre, University Children's Hospital Zürich, Zürich, Switzerland.
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13
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Gundorova P, Kuznetcova IA, Baydakova GV, Stepanova AA, Itkis YS, Kakaulina VS, Alferova IP, Lyazina LV, Andreeva LP, Kanivets I, Zakharova EY, Kutsev SI, Polyakov AV. BH4-deficient hyperphenylalaninemia in Russia. PLoS One 2021; 16:e0249608. [PMID: 33822819 PMCID: PMC8023510 DOI: 10.1371/journal.pone.0249608] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 03/22/2021] [Indexed: 02/07/2023] Open
Abstract
A timely detection of patients with tetrahydrobiopterin (BH4) -deficient types of hyperphenylalaninemia (HPABH4) is important for assignment of correct therapy, allowing to avoid complications. Often HPABH4 patients receive the same therapy as phenylalanine hydroxylase (PAH) -deficiency (phenylketonuria) patients—dietary treatment—and do not receive substitutive BH4 therapy until the diagnosis is confirmed by molecular genetic means. In this study, we present a cohort of 30 Russian patients with HPABH4 with detected variants in genes causing different types of HPA. Family diagnostics and biochemical urinary pterin spectrum analyses were carried out. HPABH4A is shown to be the prevalent type, 83.3% of all HPABH4 cases. The mutation spectrum for the PTS gene was defined, the most common variants in Russia were p.Thr106Met—32%, p.Asn72Lys—20%, p.Arg9His—8%, p.Ser32Gly—6%. We also detected 7 novel PTS variants and 3 novel QDPR variants. HPABH4 prevalence was estimated to be 0.5–0.9% of all HPA cases in Russia, which is significantly lower than in European countries on average, China, and Saudi Arabia. The results of this research show the necessity of introducing differential diagnostics for HPABH4 into neonatal screening practice.
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Affiliation(s)
| | | | | | | | | | - Victoria S. Kakaulina
- Federal State Budgetary Institution of Medical Department of Moscow “Morozov Children’s City Clinical Hospital of Medical Department of Moscow”, Moscow, Russia
| | - Irina P. Alferova
- Municipal Autonomous Health Care Institution of the Order of the Red Banner of Labor “Clinical Hospital № 1”, Chelyabinsk, Russia
| | - Lidya V. Lyazina
- Saint Petersburg State Public Health Institution "Medical Genetic Diagnostic Center”, Saint Petersburg, Russia
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14
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Manzoni F, Salvatici E, Burlina A, Andrews A, Pasquali M, Longo N. Retrospective analysis of 19 patients with 6-Pyruvoyl Tetrahydropterin Synthase Deficiency: Prolactin levels inversely correlate with growth. Mol Genet Metab 2020; 131:380-389. [PMID: 33234470 PMCID: PMC7749858 DOI: 10.1016/j.ymgme.2020.11.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/10/2020] [Accepted: 11/11/2020] [Indexed: 11/27/2022]
Abstract
BACKGROUND Pyruvoyl Tetrahydropterin Synthase (PTPS) Deficiency is the most common form of BH4 deficiency resulting in hyperphenylalaninemia. It can have variable clinical severity and there is limited information on the clinical presentation, natural history and effectiveness of newborn screening for this condition. METHODS Retrospective data (growth and clinical parameters, biochemical and genetic testing results, treatment) were collected from 19 patients with PTPS deficiency in different centers, to evaluate biochemical and clinical outcomes. Descriptive statistics was used for qualitative variables, while linear regression analysis was used to correlate quantitative variables. RESULTS Patients with PTPS deficiency had an increased incidence of prematurity (4/18) with an average gestational age only mildly reduced (37.8 ± 2.4 weeks) and low birth weight (-1.14 ± 0.97 SD below that predicted for gestational age). With time, weight and height approached normal. VALUES All patients were identified by newborn screening for an elevated phenylalanine level. However, phenylalanine levels were normal in two whose testing was performed at or before 24 h of age. Sapropterin dihydrochloride treatment normalized phenylalanine levels. Molecular testing identified novel variants in the PTS gene, some of which present in more than one affected family. The neurotransmitter derivatives 5-hydroxyindoleacetic acid (5HIAA) and homovanillic acid (HVA) in the CSF were decreased in most cases except in 2 families with the peripheral form of PTPS deficiency. With time, HVA and 5HIAA became abnormally low in two of these patients requiring therapy. Prolactin (whose secretion is inhibited by dopamine) levels were elevated in several patients with PTPS deficiency and inversely correlated with the z-scores for height (p < 0.01) and weight (p < 0.05). Most patients with PTPS deficiency had delayed development early in life, improving around school age with IQs mostly in the normal range, with a small decline in older individuals. From a neurological standpoint, most patients had normal brain MRI and minor EEG anomalies, although some had persistent neurological symptoms. DISCUSSION Patients with PTPS deficiency have not only an increased incidence of prematurity, but also decreased birth weight when corrected for gestational age. Hyperphenylalaninemia can be absent in the first day of life. Therapy with sapropterin dihydrochloride normalizes phenylalanine levels and neurotransmitter precursors can improve CSF neurotransmitter metabolites levels. Insufficient dopaminergic stimulation (as seen from elevated prolactin) might result in decreased height in patients with PTPS deficiency. Despite early delays in development, many patients can achieve independence in adult life, with usually normal neuroimaging and EEG.
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Affiliation(s)
- Francesca Manzoni
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA; Clinical Department of Neuropsychiatry, San Paolo Hospital, University of Milan, Milan, Italy; Division of Inherited Metabolic Diseases, Department of Diagnostic Services, University Hospital, Padua, Italy
| | - Elisabetta Salvatici
- Clinical Department of Pediatrics, San Paolo Hospital, University of Milan, Milan, Italy
| | - Alberto Burlina
- Division of Inherited Metabolic Diseases, Department of Diagnostic Services, University Hospital, Padua, Italy
| | - Ashley Andrews
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Marzia Pasquali
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA; Department of Pathology, University of Utah, Salt Lake City, UT, USA
| | - Nicola Longo
- Division of Medical Genetics/Pediatrics, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA; Department of Pathology, University of Utah, Salt Lake City, UT, USA..
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15
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Carducci C, Amayreh W, Ababneh H, Mahasneh A, Al Rababah B, Al Qaqa K, Al Aqeel M, Artiola C, Tolve M, D'Amici S, Shen N, Yu Y, Hillert A, Himmelreich N, Okun JG, Hoffmann GF, Blau N. Molecular genetics of phenylketonuria and tetrahydrobiopterin deficiency in Jordan. JIMD Rep 2020; 55:59-67. [PMID: 32905092 PMCID: PMC7463056 DOI: 10.1002/jmd2.12130] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 04/27/2020] [Accepted: 05/04/2020] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Information regarding the prevalence of PKU in the Middle East in comparison to other world regions is scarce, which might be explained by difficulties in the implementation of national newborn screening programs. OBJECTIVE This study seeks for the first time to genotype and biochemically characterize patients diagnosed with hyperphenylalaninemia (HPA) at the Pediatric Metabolic Genetics Clinic at the King Hussein Medical Center, Amman, Jordan. METHODS A total of 33 patients with HPA and 55 family members were investigated for pterins (neopterin and biopterin) and dihydropteridine reductase (DHPR) activity in dried blood spots. Patients with HPA were genotyped for phenylketonuria (PKU) and the genes involved in tetrahydrobiopterin (BH4) metabolism. RESULTS In total 20 patients were diagnosed with PKU due to phenylalanine hydroxylase (PAH) deficiency, 2 with GTP cyclohydrolase I (GTPCH) deficiency, 6 with DHPR deficiency, and 3 with the 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency. Diagnosis was not possible in 2 patients. This study documents a high percentage of BH4 deficiencies within HPA patients. With one exception, all patients were homozygous for particular gene variants. CONCLUSIONS This approach enables differentiation between PKU and BH4 deficiencies and, thus, allows for critical selection of a specific treatment strategies.
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Affiliation(s)
- Carla Carducci
- Department of Experimental MedicineUniversity of Rome “La Sapienza”RomeItaly
| | - Wajdi Amayreh
- Queen Rania Children Hospital, King Hussein Medical CentreAmmanJordan
- Princess Haya Biotechnology CentreJordan University of Science and TechnologyIrbidJordan
| | - Haneen Ababneh
- Princess Haya Biotechnology CentreJordan University of Science and TechnologyIrbidJordan
- Department of Biotechnology and Genetic EngineeringJordan University of Science and TechnologyIrbidJordan
| | - Amjad Mahasneh
- Princess Haya Biotechnology CentreJordan University of Science and TechnologyIrbidJordan
- Department of Biotechnology and Genetic EngineeringJordan University of Science and TechnologyIrbidJordan
| | - Buthaina Al Rababah
- Princess Haya Biotechnology CentreJordan University of Science and TechnologyIrbidJordan
| | - Kefah Al Qaqa
- Queen Rania Children Hospital, King Hussein Medical CentreAmmanJordan
| | - Momen Al Aqeel
- Queen Rania Children Hospital, King Hussein Medical CentreAmmanJordan
| | - Cristiana Artiola
- Department of Experimental MedicineUniversity of Rome “La Sapienza”RomeItaly
| | - Manuela Tolve
- Department of Experimental MedicineUniversity of Rome “La Sapienza”RomeItaly
| | - Sirio D'Amici
- Department of Experimental MedicineUniversity of Rome “La Sapienza”RomeItaly
| | - Nan Shen
- Department of Rehabilitation MedicineXin Hua Hospital affiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina
| | - Yongguo Yu
- Department of Pediatric Endocrinology and Genetic MetabolismShanghai Institute for Pediatric Research, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghaiChina
| | - Alicia Hillert
- Dietmar Hopp Metabolic Center and Centre for Pediatrics and Adolescent MedicineUniversity Hospital HeidelbergHeidelbergGermany
| | - Nastassja Himmelreich
- Dietmar Hopp Metabolic Center and Centre for Pediatrics and Adolescent MedicineUniversity Hospital HeidelbergHeidelbergGermany
| | - Jürgen G. Okun
- Dietmar Hopp Metabolic Center and Centre for Pediatrics and Adolescent MedicineUniversity Hospital HeidelbergHeidelbergGermany
| | - Georg F. Hoffmann
- Dietmar Hopp Metabolic Center and Centre for Pediatrics and Adolescent MedicineUniversity Hospital HeidelbergHeidelbergGermany
| | - Nenad Blau
- Dietmar Hopp Metabolic Center and Centre for Pediatrics and Adolescent MedicineUniversity Hospital HeidelbergHeidelbergGermany
- Division of MetabolismUniversity Children's HospitalZürichSwitzerland
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16
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Ivanov M, Ivanov M, Kasianov A, Rozhavskaya E, Musienko S, Baranova A, Mileyko V. Novel bioinformatics quality control metric for next-generation sequencing experiments in the clinical context. Nucleic Acids Res 2019; 47:e135. [PMID: 31511888 PMCID: PMC6868350 DOI: 10.1093/nar/gkz775] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 07/22/2019] [Accepted: 08/29/2019] [Indexed: 11/23/2022] Open
Abstract
As the use of next-generation sequencing (NGS) for the Mendelian diseases diagnosis is expanding, the performance of this method has to be improved in order to achieve higher quality. Typically, performance measures are considered to be designed in the context of each application and, therefore, account for a spectrum of clinically relevant variants. We present EphaGen, a new computational methodology for bioinformatics quality control (QC). Given a single NGS dataset in BAM format and a pre-compiled VCF-file of targeted clinically relevant variants it associates this dataset with a single arbiter parameter. Intrinsically, EphaGen estimates the probability to miss any variant from the defined spectrum within a particular NGS dataset. Such performance measure virtually resembles the diagnostic sensitivity of given NGS dataset. Here we present case studies of the use of EphaGen in context of BRCA1/2 and CFTR sequencing in a series of 14 runs across 43 blood samples and 504 publically available NGS datasets. EphaGen is superior to conventional bioinformatics metrics such as coverage depth and coverage uniformity. We recommend using this software as a QC step in NGS studies in the clinical context. Availability: https://github.com/m4merg/EphaGen or https://hub.docker.com/r/m4merg/ephagen.
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Affiliation(s)
- Maxim Ivanov
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russian Federation
| | - Mikhail Ivanov
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russian Federation
| | - Artem Kasianov
- Vavilov Institute of General Genetics, Moscow, Russian Federation
| | - Ekaterina Rozhavskaya
- Vavilov Institute of General Genetics, Moscow, Russian Federation.,Atlas Oncology Diagnostics, Ltd, Moscow, Russian Federation
| | | | - Ancha Baranova
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russian Federation.,Atlas Oncology Diagnostics, Ltd, Moscow, Russian Federation.,Research Centre for Medical Genetics, Moscow, Russian Federation.,School of Systems Biology, George Mason University, Fairfax, VA 22030, USA
| | - Vladislav Mileyko
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russian Federation.,Atlas Oncology Diagnostics, Ltd, Moscow, Russian Federation
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17
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Kuznetcova I, Gundorova P, Ryzhkova O, Polyakov A. The study of the full spectrum of variants leading to hyperphenylalaninemia have revealed 10 new variants in the PAH gene. Metab Brain Dis 2019; 34:1547-1555. [PMID: 31332730 DOI: 10.1007/s11011-019-00461-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 07/08/2019] [Indexed: 12/21/2022]
Abstract
This study presents further research into the spectrum of variants in genes responsible for the development of phenylketonuria (PKU) and hyperphenylalaninemia (HPA) in patients in Russia. After a study of 25 frequent variants, 293 patients (327 chromosomes without detected variants) from among 1265 probands still had no confirmed diagnosis. A study involving methods of next generation sequencing (NGS) of PAH, PTS, GCH1, PCBD1, QDPR, SPR and DNAJC12 genes to search for point mutations and multiplex ligation-dependent probe amplification (MLPA) methods to search for gross deletions were conducted for these patients. Among 327 chromosomes without identified variants, variants in the PAH gene were found on 260 chromosomes, and variants in the PTS gene were found on 10 chromosomes. On 10 chromosomes gross deletions by the MLPA method were detected. 104 rare variants of the РАН gene, including 10 variants not previously described, and 6 variants of the PTS gene were revealed. The NGS method revealed additional РАН gene variants on 10.3% of chromosomes and PTS gene variants on 0.4%. Gross deletions of the РАН gene were revealed in 0.5% of chromosomes. Thus, the most complete understanding of the spectrum of variants leading to the development of the PKU and HPA in Russia with the use of all methods available today has been obtained. Such a detailed study of the spectrum of rare variants on the genetic material from Russia was undertaken for the first time.
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Affiliation(s)
- I Kuznetcova
- Federal State Funded Research Institution "Research Centre of Medical Genetics", Moscow, Russian Federation.
| | - P Gundorova
- Federal State Funded Research Institution "Research Centre of Medical Genetics", Moscow, Russian Federation
| | - O Ryzhkova
- Federal State Funded Research Institution "Research Centre of Medical Genetics", Moscow, Russian Federation
| | - A Polyakov
- Federal State Funded Research Institution "Research Centre of Medical Genetics", Moscow, Russian Federation
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18
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Wang X, He Y, Jiang Y, Feng X, Zhang G, Xia Z, Zhou Y. Screening and mutation analysis of hyperphenylalaninemia in newborns from Xiamen, China. Clin Chim Acta 2019; 498:161-166. [PMID: 31445982 DOI: 10.1016/j.cca.2019.08.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/13/2019] [Accepted: 08/21/2019] [Indexed: 11/27/2022]
Abstract
In this study, we evaluated the incidence and genetic characteristics of hyperphenylalaninemia (HPA) in Xiamen, China. We analyzed the newborn screening data of HPA, obtained using a fluorometric method and tandem mass spectrometry (MS/MS), from 2013 to 2017. The suspected positive samples were further diagnosed using MassArray technology, multiplex ligation-dependent probe amplification (MLPA), and Sanger sequencing. A total of 418,831 newborns were screened, of whom 19 were diagnosed as HPA patients, with an incidence of 1:22,044. Of these HPA patients, 15 tested positive for phenylketonuria (PKU, 1:27922), and 4 tested positive for tetrahydrobiopterin deficiency (BH4D, 1:104,708). A total of 17 mutations were identified among 38 alleles in the 19 patients, with a detection rate of 94.74%, including 13 PAH and 4 PTS mutations. Among these, the c.721C>T, c.728G>A, c.1197A>T, c.611A>G and c.331C>T mutations, and the c.259C>T and c.155A>G mutations were the most prevalent PAH and PTS mutations in Xiamen, respectively. Therefore, this study systematically demonstrated the incidence and mutation spectrum of HPA in Xiamen. This information would contribute to genetic counseling, prenatal diagnosis, and management of HPA patients. Moreover, combining MS/MS technology with molecular genetic diagnosis is an effective strategy for future newborn HPA screening in Xiamen.
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Affiliation(s)
- Xudong Wang
- Department of Xiamen Newborn Screening Center, Women and Children's Hospital, School of Medicine, Xiamen University, 10 Zhenhai Road, Xiamen, Fujian 361003, China
| | - Ying He
- Department of Xiamen Newborn Screening Center, Women and Children's Hospital, School of Medicine, Xiamen University, 10 Zhenhai Road, Xiamen, Fujian 361003, China
| | - Yancheng Jiang
- Department of Laboratory Medicine, The First Hospital of Quanzhou Affiliated to Fujian Medical University, 248-252 East Street, Quanzhou, Fujian 362000, China
| | - Xiaomei Feng
- School of Life Sciences, Xiamen University, 4221-120 Xiang An Nan Road, Xiamen, Fujian Province 361005, China
| | - Guowang Zhang
- Department of Otolaryngology, Women and Children's Hospital, School of Medicine, Xiamen University, 10 Zhenhai Road, Xiamen, Fujian 361003, China
| | - Zhongmin Xia
- United Diagnostic and Research Center for Clinical Genetics, School of Public Health of Xiamen University & Women and Children's Hospital, Xiamen University, 4221-120 Xiang An Nan Road, Xiamen, Fujian 361102, China.
| | - Yulin Zhou
- United Diagnostic and Research Center for Clinical Genetics, School of Public Health of Xiamen University & Women and Children's Hospital, Xiamen University, 4221-120 Xiang An Nan Road, Xiamen, Fujian 361102, China.
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19
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Růžička M, Souček P, Kulhánek P, Radová L, Fajkusová L, Réblová K. Bending of DNA duplexes with mutation motifs. DNA Res 2019; 26:341-352. [PMID: 31230075 PMCID: PMC6704406 DOI: 10.1093/dnares/dsz013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/27/2019] [Indexed: 01/30/2023] Open
Abstract
Mutations can be induced by environmental factors but also arise spontaneously during DNA replication or due to deamination of methylated cytosines at CpG dinucleotides. Sites where mutations occur with higher frequency than would be expected by chance are termed hotspots while sites that contain mutations rarely are termed coldspots. Mutations are permanently scanned and repaired by repair systems. Among them, the mismatch repair targets base pair mismatches, which are discriminated from canonical base pairs by probing altered elasticity of DNA. Using biased molecular dynamics simulations, we investigated the elasticity of coldspots and hotspots motifs detected in human genes associated with inherited disorders, and also of motifs with Czech population hotspots and de novo mutations. Main attention was paid to mutations leading to G/T and A+/C pairs. We observed that hotspots without CpG/CpHpG sequences are less flexible than coldspots, which indicates that flexible sequences are more effectively repaired. In contrary, hotspots with CpG/CpHpG sequences exhibited increased flexibility as coldspots. Their mutability is more likely related to spontaneous deamination of methylated cytosines leading to C > T mutations, which are primarily targeted by base excision repair. We corroborated conclusions based on computer simulations by measuring melting curves of hotspots and coldspots containing G/T mismatch.
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Affiliation(s)
- Michal Růžička
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic.,Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Přemysl Souček
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Petr Kulhánek
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic.,National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Lenka Radová
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Lenka Fajkusová
- Centre of Molecular Biology and Gene Therapy, University Hospital Brno, Brno, Czech Republic
| | - Kamila Réblová
- CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
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20
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Almannai M, Felemban R, Saleh MA, Faqeih EA, Alasmari A, AlHashem A, Mohamed S, Sunbul R, Al-Murshedi F, AlThihli K, Eyaid W, Ali R, Ben-Omran T, Blau N, El-Hattab AW, Alfadhel M. 6-Pyruvoyltetrahydropterin Synthase Deficiency: Review and Report of 28 Arab Subjects. Pediatr Neurol 2019; 96:40-47. [PMID: 30926181 DOI: 10.1016/j.pediatrneurol.2019.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 02/03/2019] [Accepted: 02/10/2019] [Indexed: 01/07/2023]
Abstract
BACKGROUND Tetrahydrobiopterin is an essential cofactor for the hydroxylation of aromatic amino acids phenylalanine, tyrosine, and tryptophan. Therefore, tetrahydrobiopterin deficiency results in hyperphenylalaninemia as well as dopamine and serotonin depletion in the central nervous system. The enzyme 6-pyruvoyltetrahydropterin synthase catalyzes the second step of de novo synthesis of tetrahydrobiopterin, and its deficiency is the most frequent cause of tetrahydrobiopterin metabolism disorders. METHOD We conducted a retrospective chart review of 28 subjects from 24 families with molecularly confirmed 6-pyruvoyltetrahydropterin synthase deficiency from six centers in three Arab countries. We reviewed clinical, biochemical, and molecular data. We also reviewed previously published cohorts of subjects with 6-pyruvoyltetrahydropterin synthase deficiency. RESULTS Similar to previous observations, we show that early treatment (less than two months) is associated with better outcome. We identify eight PTS variants in 24 independent families. The most common variant is (c.238A>G; p.M80V) with an allele count of 33%. We also identify one novel variant (c.2T>G; p.?). CONCLUSION The deficiency of 6-pyruvoyltetrahydropterin synthase is relatively common in the Arab population and should be considered in individuals with hyperphenylalaninemia. More natural history studies with comprehensive biochemical and molecular genetics data are needed for a robust base for the development of future therapy.
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Affiliation(s)
- Mohammed Almannai
- Section of Medical Genetics, Children's Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Rana Felemban
- Section of Medical Genetics, Children's Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Mohammed A Saleh
- Section of Medical Genetics, Children's Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Eissa A Faqeih
- Section of Medical Genetics, Children's Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Ali Alasmari
- Section of Medical Genetics, Children's Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Amal AlHashem
- Department of Pediatric, Prince Sultan Medical Military City, Riyadh, Saudi Arabia; Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Sarar Mohamed
- Department of Pediatric, Prince Sultan Medical Military City, Riyadh, Saudi Arabia
| | - Rawda Sunbul
- Pediatrics Medical Genetic Unit (PMGU), Pediatrics Department, Qatif Central Hospital, Qatif, Saudi Arabia
| | - Fathiya Al-Murshedi
- Department of Genetics, College of Medicine, Sultan Qaboos University, Muscat, Sultanate of Oman
| | - Khalid AlThihli
- Department of Genetics, College of Medicine, Sultan Qaboos University, Muscat, Sultanate of Oman
| | - Wafaa Eyaid
- Division of Genetics, Department of Pediatrics, King Abdulaziz Medical City, Ministry of National Guard-Health Affairs (MNGHA), Riyadh, Saudi Arabia
| | - Rehab Ali
- Clinical and Metabolic Genetics Section, Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
| | - Tawfeg Ben-Omran
- Clinical and Metabolic Genetics Section, Department of Pediatrics, Hamad Medical Corporation, Doha, Qatar
| | - Nenad Blau
- Dietmar-Hopp-Metabolic Center, University Children's Hospital, Heidelberg, Germany; Division of Metabolism, University Children's Hospital Zurich, Switzerland
| | - Ayman W El-Hattab
- Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates; Genetics Clinics, KidsHeart Medical Center, Dubai, United Arab Emirates
| | - Majid Alfadhel
- Division of Genetics, Department of Pediatrics, King Abdulaziz Medical City, Ministry of National Guard-Health Affairs (MNGHA), Riyadh, Saudi Arabia; King Abdullah International Medical Research Center (KAIMRC), Riyadh, Saudi Arabia; College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
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21
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Muniz JR, Szeto NWS, Frise R, Lee WH, Wang XS, Thöny B, Himmelreich N, Blau N, Hsiao KJ, Liu TT, Gileadi O, Oppermann U, Von Delft F, Yue WW, Tang NLS. Role of protein structure in variant annotation: structural insight of mutations causing 6-pyruvoyl-tetrahydropterin synthase deficiency. Pathology 2019; 51:274-280. [DOI: 10.1016/j.pathol.2018.11.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 11/13/2018] [Accepted: 11/19/2018] [Indexed: 10/27/2022]
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22
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Li N, Yu P, Rao B, Deng Y, Guo Y, Huang Y, Ding L, Zhu J, Yang H, Wang J, Guo J, Chen F, Liu Z. Molecular genetics of tetrahydrobiopterin deficiency in Chinese patients. J Pediatr Endocrinol Metab 2018; 31:911-916. [PMID: 30001213 DOI: 10.1515/jpem-2018-0037] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Accepted: 05/14/2018] [Indexed: 11/15/2022]
Abstract
Background The overall incidence of hyperphenylalaninemia (HPA) in China is 1:11,763, with tetrahydrobiopterin (BH4) deficiency accounting for 8.55% of patients with HPA in the mainland. Much progress has been made in the diagnosis and treatment of BH4 deficiency with the introduction of neonatal screening in China. However, the screening rate is still low and screening is not universally available. Methods A total of 44 BH4-deficient patients were enrolled in this study, of which 39 were diagnosed with BH4 deficiency, while the remaining five showed typical characteristics of BH4 deficiency at a later period. The entire coding regions and adjacent intronic regions of GCH1, PTS, PCBD1 and QDPR genes were analyzed using target sequencing. Results Nineteen (n=19) different mutations in the PTS gene including four novel mutations and one mutation in QDPR were identified. p.P87S, p.D96N, IVS1-291A>G, p.N52S, p.K91R, p.V56M, p.T106M and p.F40GfsX53 in PTS were the prevalent mutations with ≥3% relative frequency. The mutation p.R221X in the QDPR gene was found with relatively lower frequencies (2.27%). The remaining 12 mutations in PTS were found at relative frequencies of 1.14%. Conclusions The results could be of value for genetic counseling and prenatal diagnosis in the patients' families and for the molecular diagnosis of BH4 deficiencies. Furthermore, four novel mutations expand and improve the PTS mutation database.
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Affiliation(s)
- Nana Li
- National Center for Birth Defects Monitoring, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, P.R. China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, P.R. China
| | - Ping Yu
- National Center for Birth Defects Monitoring, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, P.R. China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, P.R. China
| | - Bin Rao
- BGI-Shenzhen, Shenzhen, P.R. China.,China National GeneBank, BGI-Shenzhen, Shenzhen, P.R. China
| | - Ying Deng
- National Center for Birth Defects Monitoring, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, P.R. China
| | - Yixiong Guo
- National Center for Birth Defects Monitoring, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, P.R. China
| | - Yushan Huang
- BGI-Shenzhen, Shenzhen, P.R. China.,China National GeneBank, BGI-Shenzhen, Shenzhen, P.R. China
| | - Lijie Ding
- BGI-Shenzhen, Shenzhen, P.R. China.,China National GeneBank, BGI-Shenzhen, Shenzhen, P.R. China
| | - Jun Zhu
- National Center for Birth Defects Monitoring, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, P.R. China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, Sichuan, P.R. China
| | - Huanming Yang
- BGI-Shenzhen, Shenzhen, P.R. China.,James D. Watson Institute of Genome Sciences, Hangzhou, P.R. China
| | - Jian Wang
- BGI-Shenzhen, Shenzhen, P.R. China.,James D. Watson Institute of Genome Sciences, Hangzhou, P.R. China
| | - Jian Guo
- BGI-Shenzhen, Building 11, Beishan Industrial Zone, Yantian, Shenzhen, Guangdong, P.R. China, Phone: 86-15914038192.,BGI-Shenzhen, Building 11, Beishan Industrial Zone, Yantian, Shenzhen, Guangdong, P.R. China, Phone: 86-13428735579.,China National GeneBank, BGI-Shenzhen, Shenzhen, Guangdong, P.R. China
| | - Fang Chen
- BGI-Shenzhen, Building 11, Beishan Industrial Zone, Yantian, Shenzhen, Guangdong, P.R. China, Phone: 86-15914038192.,BGI-Shenzhen, Building 11, Beishan Industrial Zone, Yantian, Shenzhen, Guangdong, P.R. China, Phone: 86-13428735579.,China National GeneBank, BGI-Shenzhen, Shenzhen, Guangdong, P.R. China
| | - Zhen Liu
- National Center for Birth Defects Monitoring, West China Second University Hospital, Sichuan University, 20, Section 3, Ren Min South Road, Chengdu, Sichuan, P.R. China, Phone: 86-028-85502490, Fax: 86-028-85501386.,Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, P.R. China
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23
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Fernández-Lainez C, Ibarra-González I, Alcántara-Ortigoza MÁ, Fernández-Hernández L, Enríquez-Flores S, González-Del Ángel A, Blau N, Thöny B, Guillén-López S, Belmont-Martínez L, Ruiz-García M, Vela-Amieva M. Mutational spectrum of PTS gene and in silico pathological assessment of a novel variant in Mexico. Brain Dev 2018; 40:530-536. [PMID: 29685341 DOI: 10.1016/j.braindev.2018.03.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 03/28/2018] [Accepted: 03/29/2018] [Indexed: 01/23/2023]
Abstract
BACKGROUND Tetrahydrobiopterin (BH4) is the cofactor for 6-pyruvoyl-tetrahydropterin synthase (PTPS); it is involved in BH4 biosynthesis and is encoded by PTS gene. Its deficiency (PTPSD) is characterized by hyperphenylalaninemia (HPA) and deficit in central monoamine neurotransmitters. We describe the clinical and mutational spectrum of five patients with PTPSD, from four unrelated Mexican families. All patients had symptomatic diagnosis and presented severe early neurological manifestations and HPA. METHODS Clinical and biochemical data from studied patients were recorded. Responsible PTPSD genotypes was determined by direct and bidirectional Sanger DNA sequencing of the six PTS coding exons and their exon-intron borders, and these were directly searched in the available relatives. The novel PTS missense variant [NM_3000317.2:331G > T, p.(Ala111Ser)] was subjected to in silico, to predict a possible deleterious effect. RESULTS Diminished fetal movements were perceived as a uniform characteristic in the studied group. DNA sequencing showed two known p.(Arg25∗) and p.(Val132TyrFs∗19) and the novel missense p.(Ala111Ser) PTS variants, the latter representing potentially a frequent PTPSD-responsible allele (50%, 4/8) in Mexican patients. In silico protein modeling analysis of the p.(Ala111Ser) variant revealed loss of hydrophobic interactions between the alanine and neighboring valines, suggesting that these changes in polarity may be detrimental for enzyme function, structure and/or stability. CONCLUSIONS This work contributes to the knowledge of PTPS molecular spectrum. The delayed diagnosis of these patients emphasizes the importance of considering BH4 metabolism defects in the differential diagnosis of HPA, especially for countries that are beginning their HPA newborn screening programs.
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Affiliation(s)
- Cynthia Fernández-Lainez
- Laboratory of Inborn Errors of Metabolism and Screening, National Institute of Pediatrics, Mexico City, Mexico
| | - Isabel Ibarra-González
- Nutritional Genetics Unit, Biomedical Research Institute, UNAM-National Institute of Pediatrics, Mexico City, Mexico
| | | | - Liliana Fernández-Hernández
- Laboratory of Molecular Biology, Department of Genetics, National Institute of Pediatrics, Mexico City, Mexico
| | - Sergio Enríquez-Flores
- Division of Experimental Medicine, National Institute of Pediatrics, Mexico City, Mexico
| | - Ariadna González-Del Ángel
- Laboratory of Molecular Biology, Department of Genetics, National Institute of Pediatrics, Mexico City, Mexico
| | - Nenad Blau
- Dietmar-Hopp-Metabolic Center, University Children's Hospital, Heidelberg, Germany
| | - Beat Thöny
- Division of Metabolism and Children's Research Centre (CRC), University Children's Hospital, Zurich, Switzerland
| | - Sara Guillén-López
- Laboratory of Inborn Errors of Metabolism and Screening, National Institute of Pediatrics, Mexico City, Mexico
| | - Leticia Belmont-Martínez
- Laboratory of Inborn Errors of Metabolism and Screening, National Institute of Pediatrics, Mexico City, Mexico
| | - Matilde Ruiz-García
- Department of Neurology, National Institute of Pediatrics, Mexico City, Mexico
| | - Marcela Vela-Amieva
- Laboratory of Inborn Errors of Metabolism and Screening, National Institute of Pediatrics, Mexico City, Mexico.
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24
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Wang ZW, Jiang SW, Zhou BC. PAH mutation spectrum and correlation with PKU manifestation in north Jiangsu province population. Kaohsiung J Med Sci 2017; 34:89-94. [PMID: 29413232 DOI: 10.1016/j.kjms.2017.09.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/08/2017] [Accepted: 09/15/2017] [Indexed: 01/16/2023] Open
Abstract
Phenylketonuria (PKU) is a common autosomal recessive disorder of phenylalanine metabolism and mainly results a deficiency of phenylalanine hydroxylase gene (PAH). The incidence of various PAH mutations have race and ethnicity differences. We report a spectrum of PAH mutations complied from 35 PKU children who are all Chinese Han population from north Jiangsu in this study. All 13 exons and their flanking intron sequences of PAH were determined by Ion Torrent PGM™ sequencing. The relationship of genotype and phenotype was analyzed based on the sum of the arbitrary value (AV) values of the two alleles. We identified 61 mutations, with a frequency of 87.14%, among 70 alleles of 35 patients. The most prevalent mutations were R243Q (26.23%), R241C (9.84%) and V399V (8.20%). Furthermore, the consistency between prediction of the biochemical phenotype and the observed phenotype was 81.25%, with the highest consistency observed in classic PKU (87.50%). A significant correlation was found between pretreatment levels of phenylalanine and AV sum (r = -0.87, P < 0.05). Finally, our study constructs PAH mutation spectrum by next generation sequencing (NGS), and reveals that the PAH genotypes and biochemical phenotypes were significantly correlated. These offers facilitate the provision of appropriate genetic counseling for PKU patients.
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Affiliation(s)
- Zhen-Wen Wang
- Department of Medical Laboratory, Lianyungang Maternal and Child Health Hospital, Lianyungang, Jiangsu, China
| | - Shi-Wen Jiang
- Department of Biomedical Science, Mercer University School of Medicine, Macon, GA, USA
| | - Bao-Cheng Zhou
- Department of Medical Laboratory, Lianyungang Maternal and Child Health Hospital, Lianyungang, Jiangsu, China.
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25
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Růžička M, Kulhánek P, Radová L, Čechová A, Špačková N, Fajkusová L, Réblová K. DNA mutation motifs in the genes associated with inherited diseases. PLoS One 2017; 12:e0182377. [PMID: 28767725 PMCID: PMC5540541 DOI: 10.1371/journal.pone.0182377] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 07/17/2017] [Indexed: 11/18/2022] Open
Abstract
Mutations in human genes can be responsible for inherited genetic disorders and cancer. Mutations can arise due to environmental factors or spontaneously. It has been shown that certain DNA sequences are more prone to mutate. These sites are termed hotspots and exhibit a higher mutation frequency than expected by chance. In contrast, DNA sequences with lower mutation frequencies than expected by chance are termed coldspots. Mutation hotspots are usually derived from a mutation spectrum, which reflects particular population where an effect of a common ancestor plays a role. To detect coldspots/hotspots unaffected by population bias, we analysed the presence of germline mutations obtained from HGMD database in the 5-nucleotide segments repeatedly occurring in genes associated with common inherited disorders, in particular, the PAH, LDLR, CFTR, F8, and F9 genes. Statistically significant sequences (mutational motifs) rarely associated with mutations (coldspots) and frequently associated with mutations (hotspots) exhibited characteristic sequence patterns, e.g. coldspots contained purine tract while hotspots showed alternating purine-pyrimidine bases, often with the presence of CpG dinucleotide. Using molecular dynamics simulations and free energy calculations, we analysed the global bending properties of two selected coldspots and two hotspots with a G/T mismatch. We observed that the coldspots were inherently more flexible than the hotspots. We assume that this property might be critical for effective mismatch repair as DNA with a mutation recognized by MutSα protein is noticeably bent.
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Affiliation(s)
- Michal Růžička
- CEITEC—Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, Czech Republic
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, Brno, Czech Republic
| | - Petr Kulhánek
- CEITEC—Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, Czech Republic
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, Brno, Czech Republic
| | - Lenka Radová
- CEITEC—Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, Czech Republic
| | - Andrea Čechová
- CEITEC—Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, Czech Republic
| | - Naďa Špačková
- Department of Condensed Matter Physics, Faculty of Science, Masaryk University, Kotlářská 2, Brno, Czech Republic
| | - Lenka Fajkusová
- Centre of Molecular Biology and Gene Therapy, University Hospital Brno and Masaryk University, Jihlavská 20, Brno, Czech Republic
| | - Kamila Réblová
- CEITEC—Central European Institute of Technology, Masaryk University, Kamenice 5, Brno, Czech Republic
- * E-mail:
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26
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Han B, Zou H, Han B, Zhu W, Cao Z, Liu Y. Diagnosis, treatment and follow-up of patients with tetrahydrobiopterin deficiency in Shandong province, China. Brain Dev 2015; 37:592-8. [PMID: 25304915 DOI: 10.1016/j.braindev.2014.09.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/05/2014] [Accepted: 09/17/2014] [Indexed: 11/29/2022]
Abstract
OBJECTIVES To summarize the clinical and biochemical data, mutation analysis, treatment, outcome and the follow-up data of patients with BH4 deficiency from 2004 to 2012 in Shandong province, China. METHODS We analyzed the clinical, biochemical and treatment data of 40 patients with BH4 deficiency. Urinary neopterin and biopterin were analyzed. Further BH4 loading tests were performed in suspected patients with abnormal urinary pterin profiles. The patients with BH4 deficiency were treated with BH4 and neurotransmitter after diagnosis. Blood phenylalanine level, clinical symptoms and mental development were followed up. RESULTS 40 cases with BH4 deficiency were identified and all classified as PTPS deficiency between 2004 and 2012 in Shandong province, China. They were diagnosed at the age of 20d - 41m and most patients received treatment with BH4, l-dopa and 5-HTP after diagnosis. Seven different mutations (P87S, K91R, T106M, D96N, N52S, S21R, and L127F) were detected in 11 patients. But outcome assessments were not always available. We obtained 19 records of DQ/IQ assessment. In 9 patients (7 early and 2 late diagnosed) no development delay is observed, while in 10 patients (8 early and 2 late diagnosed) development was delayed. CONCLUSIONS Our study emphasized that screening for BH4 deficiency should be carried out in all patients with HPA in order to minimize misdiagnosis. Although the outcomes of BH4 deficiency are highly variable, early diagnosis and treatment is essential for good outcomes.
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Affiliation(s)
- Bingjuan Han
- Jinan Maternal and Child Care Hospital, Jinan 250001, Shandong Province, China
| | - Hui Zou
- Jinan Maternal and Child Care Hospital, Jinan 250001, Shandong Province, China
| | - Bingchao Han
- Jinan Maternal and Child Care Hospital, Jinan 250001, Shandong Province, China
| | - Weiwei Zhu
- Jinan Central Hospital, Jinan 250013, Shandong Province, China
| | - Zhiyang Cao
- Nanjing Jiangning Hospital, Affiliated to Nanjing Medical University, Nanjing 211100, Jiangsu Province, China.
| | - Yingxia Liu
- Jinan Maternal and Child Care Hospital, Jinan 250001, Shandong Province, China; Department of Immunology, Nanjing Medical University, Nanjing 210029, Jiangsu Province, China.
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27
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Park J, Kim M, Jang W, Chae H, Kim Y, Chung NG, Lee JW, Cho B, Jeong DC, Park IY, Park MS. Founder haplotype analysis of Fanconi anemia in the Korean population finds common ancestral haplotypes for a FANCG variant. Ann Hum Genet 2015; 79:153-61. [PMID: 25703136 DOI: 10.1111/ahg.12097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 11/19/2014] [Indexed: 11/28/2022]
Abstract
A common ancestral haplotype is strongly suggested in the Korean and Japanese patients with Fanconi anemia (FA), because common mutations have been frequently found: c.2546delC and c.3720_3724delAAACA of FANCA; c.307+1G>C, c.1066C>T, and c.1589_1591delATA of FANCG. Our aim in this study was to investigate the origin of these common mutations of FANCA and FANCG. We genotyped 13 FA patients consisting of five FA-A patients and eight FA-G patients from the Korean FA population. Microsatellite markers used for haplotype analysis included four CA repeat markers which are closely linked with FANCA and eight CA repeat markers which are contiguous with FANCG. As a result, Korean FA-A patients carrying c.2546delC or c.3720_3724delAAACA did not share the same haplotypes. However, three unique haplotypes carrying c.307+1G>C, c.1066C > T, or c.1589_1591delATA, that consisted of eight polymorphic loci covering a flanking region were strongly associated with Korean FA-G, consistent with founder haplotypes reported previously in the Japanese FA-G population. Our finding confirmed the common ancestral haplotypes on the origins of the East Asian FA-G patients, which will improve our understanding of the molecular population genetics of FA-G. To the best of our knowledge, this is the first report on the association between disease-linked mutations and common ancestral haplotypes in the Korean FA population.
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Affiliation(s)
- Joonhong Park
- Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; Catholic Genetic Laboratory Center, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
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28
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Inherited metabolic diseases in the Southern Chinese population: spectrum of diseases and estimated incidence from recurrent mutations. Pathology 2015; 46:375-82. [PMID: 24992243 DOI: 10.1097/pat.0000000000000140] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Inherited metabolic diseases (IMDs) are a large group of rare genetic diseases. The spectrum and incidences of IMDs differ among populations, which has been well characterised in Caucasians but much less so in Chinese. In a setting of a University Hospital Metabolic Clinic in Hong Kong, over 100 patients with IMDs have been seen during a period of 13 years (from 1997 to 2010). The data were used to define the spectrum of diseases in the Southern Chinese population. Comparison with other populations revealed a unique spectrum of common IMDs. Furthermore, the incidence of the common IMDs was estimated by using population carrier frequencies of known recurrent mutations. Locally common diseases (their estimated incidence) include (1) glutaric aciduria type 1 (∼1/60,000), (2) multiple carboxylase deficiency (∼1/60,000), (3) primary carnitine deficiency (∼1/60,000), (4) carnitine-acylcarnitine translocase deficiency (∼1/60,000), (5) glutaric aciduria type 2 (∼1/22,500), (6) citrin deficiency (∼1/17,000), (7) tetrahydrobiopterin-deficient hyperphenylalaninaemia due to 6-pyruvoyl-tetrahydropterin synthase deficiency (∼1/60,000), (8) glycogen storage disease type 1 (∼1/150,000). In addition, ornithine carbamoyltransferase deficiency and X-linked adrenoleukodystrophy are common X-linked diseases. Findings of the disease spectrum and treatment outcome are summarised here which may be useful for clinical practice. In addition, data will also be useful for policy makers in planning of newborn screening programs and resource allocation.
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29
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Chiu YH, Liu YN, Liao WL, Chang YC, Lin SP, Hsu CC, Chiu PC, Niu DM, Wang CH, Ke YY, Chien YH, Hsiao KJ, Liu TT. Two frequent mutations associated with the classic form of propionic acidemia in Taiwan. Biochem Genet 2014; 52:415-29. [PMID: 24863100 DOI: 10.1007/s10528-014-9657-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 04/18/2014] [Indexed: 12/15/2022]
Abstract
Propionyl-CoA carboxylase (PCC) is involved in the catabolism of branched chain amino acids, odd-numbered fatty acids, cholesterol, and other metabolites. PCC consists of two subunits, α and β, encoded by the PCCA and PCCB genes, respectively. Mutations in the PCCA or PCCB subunit gene may lead to propionic acidemia. In this study, we performed mutation analysis on ten propionic acidemia patients from eight unrelated and nonconsanguineous families in Taiwan. Two PCCA mutations, c.229C→T (p.R77W) and c.1262A→C (p.Q421P), were identified in a PCCA-deficient patient. Six mutations in the PCCB gene, including c.-4156_183+3713del, c.580T→C (p.S194P), c.838dup (p.L280Pfs 11), c.1301C→T (p.A434V), c.1316A→G (P.Y439C), and c.1534C→T (p.R512C), were identified in seven PCCB-deficient families. The c.-4156_183+3713del mutation is the first known large deletion that affects the PCCB gene functions. Furthermore, the c.1301C→T and c.-4156_183+3713del mutations in the PCCB gene have not been reported previously. Clinical features demonstrated that these two frequent mutations are associated with low enzyme activity and a classic propionic acidemia phenotype.
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Affiliation(s)
- Yen-Hui Chiu
- Department of Education and Research, Taipei City Hospital, Taipei, Taiwan
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Gu Y, Lu K, Yang G, Cen Z, Yu L, Lin L, Hao J, Yang Z, Peng J, Cui S, Huang J. Mutation spectrum of six genes in Chinese phenylketonuria patients obtained through next-generation sequencing. PLoS One 2014; 9:e94100. [PMID: 24705691 PMCID: PMC3976377 DOI: 10.1371/journal.pone.0094100] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Accepted: 03/11/2014] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The identification of gene variants plays an important role in the diagnosis of genetic diseases. METHODOLOGY/PRINCIPAL FINDINGS To develop a rapid method for the diagnosis of phenylketonuria (PKU) and tetrahydrobiopterin (BH4) deficiency, we designed a multiplex, PCR-based primer panel to amplify all the exons and flanking regions (50 bp average) of six PKU-associated genes (PAH, PTS, GCH1, QDPR, PCBD1 and GFRP). The Ion Torrent Personal Genome Machine (PGM) System was used to detect mutations in all the exons of these six genes. We tested 93 DNA samples from blood specimens from 35 patients and their parents (32 families) and 26 healthy adults. Using strict bioinformatic criteria, this sequencing data provided, on average, 99.14% coverage of the 39 exons at more than 70-fold mean depth of coverage. We found 23 previously documented variants in the PAH gene and six novel mutations in the PAH and PTS genes. A detailed analysis of the mutation spectrum of these patients is described in this study. CONCLUSIONS/SIGNIFICANCE These results were confirmed by Sanger sequencing. In conclusion, benchtop next-generation sequencing technology can be used to detect mutations in monogenic diseases and can detect both point mutations and indels with high sensitivity, fidelity and throughput at a lower cost than conventional methods in clinical applications.
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Affiliation(s)
- Ying Gu
- Prenatal Diagnosis Center, Maternal and Child Health Care Hospital, Lianyungang, Jiangsu, China
| | - Kangmo Lu
- Prenatal Diagnosis Center, Chengdu Women's and Children's Central Hospital, Chengdu, Sichuan, China
| | | | - Zhong Cen
- Shanghai Find Bio-Tech Co., Ltd., Shanghai, China
| | - Li Yu
- Life Technologies Company, Shanghai, China
| | - Lin Lin
- Shanghai Find Bio-Tech Co., Ltd., Shanghai, China
| | - Jing Hao
- Shanghai Find Bio-Tech Co., Ltd., Shanghai, China
| | - Zhigang Yang
- Shanghai Find Bio-Tech Co., Ltd., Shanghai, China
| | - Jiabao Peng
- Shanghai Find Bio-Tech Co., Ltd., Shanghai, China
| | - Shujian Cui
- Shanghai Find Bio-Tech Co., Ltd., Shanghai, China
| | - Jian Huang
- National Engineering Center for Biochip at Shanghai, Shanghai, China
- Shanghai-MOST Key Laboratory for Disease and Health Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China
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Ye J, Yang Y, Yu W, Zou H, Jiang J, Yang R, Shang S, Gu X. Demographics, diagnosis and treatment of 256 patients with tetrahydrobiopterin deficiency in mainland China: results of a retrospective, multicentre study. J Inherit Metab Dis 2013; 36:893-901. [PMID: 23138986 DOI: 10.1007/s10545-012-9550-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 09/28/2012] [Accepted: 10/08/2012] [Indexed: 11/28/2022]
Abstract
BACKGROUND National coverage of neonatal screening for hyperphenylalaninaemia (HPA) in China is still low and tests to differentiate causes of HPA are not performed in many centres. This study aimed to describe the demographics, geographic distribution, diagnosis, treatment and clinical outcomes of treatment, including intellectual development, in patients with tetrahydrobiopterin (BH4) deficiency in mainland China. METHODS This was a retrospective, multicentre, chart review in patients with BH4 deficiency across mainland China born 1985-2010. RESULTS Two hundred fifty six patients were included; 59.9 % (267/446) of parents were from eastern China. Median (interquartile range) age at diagnosis decreased from 12.0 (5.5, 102.0) months to 2.0 (1.0, 3.5) months in patients born 1985-1999 (n = 28) and 2005-2010 (n = 152), respectively. 6-Pyruvoyl-tetrahydropterin synthase (PTPS) deficiency was the primary cause of BH4 deficiency (96.0 %); four hotspot mutations accounted for 76.6 % of PTS gene mutations; two novel variants in the QDPR gene were identified. Most patients (83.6 %) received treatment with BH4, L-dopa, 5-hydroxytryptophan and/or diet therapy. Target blood Phe concentration was confirmed at 88.9 % of visits; median (Q1, Q3) blood Phe concentration was 106.8 (73.0, 120.0) μmol/L during therapy and 117.0 (67.1, 120.0) μmol/L at last visit. Median (Q1, Q3) WISC IQ score was 80.0 (69.0, 90.0) in 33 patients. DQ scores were within normal range (≥85) for 37/59 (62.7 %) patients. Physical development indicators were within normal ranges. Treatment-related adverse events, reported in 20/256 (7.8 %) patients, were mild-to-moderate in severity. CONCLUSION This study provides valuable information on the current and historical situation of BH4 deficiency in mainland China.
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Affiliation(s)
- Jun Ye
- Xinhua Hospital affiliated to Shanghai JiaoTong University School of Medicine, Shanghai, PR China
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Shintaku H. Commentary on the mutation spectrum of and founder effects affecting the PTS gene in East-Asian populations. J Hum Genet 2012; 57:159-60. [DOI: 10.1038/jhg.2011.153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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