Hurler Syndrome: a Biochemically Confirmed Case in Dominican Republic

Abstract Mucopolysaccharidosis (MPS) is a group of metabolic disorders caused by the deficiency or complete absence of certain lysosomal enzymes responsible for the breakdown of mucopolysaccharides, causing an accumulation of glycosaminoglycans (GAGs) throughout the body. Mucopolysaccharidosis type I (MPS I), also called Hurler syndrome, is an autosomal recessive lysosomal storage disorder resulting from a deficiency of the enzyme α-L-iduronidase. This report aims to present the clinical findings and diagnosis of a 21-month-old female with no history of similar cases in their previous generations. The diagnosis was considered based on the clinical and radiological characteristics of Hurler syndrome (HS) and confirmed biochemically, becoming the first confirmed case in the Dominican Republic.

Encefalocele en paciente con síndrome de Hurler: descripción y revisión de alternativas terapéuticas / Encephalocele in a patient with Hurler syndrome: description and therapeutic alternatives review

Introducción: el síndrome de Hurler es la forma más grave de la mucopolisacaridosis I. El depósito de heparán y dermatán sulfato en las meninges favorece el desarrollo de hidrocefalia y, a su vez, de meningoencefaloceles. Caso clínico: se describe el caso de una paciente de 23 años con este síndrome y un encefalocele nasosinusal intervenido mediante cirugía endoscópica nasosinusal y posterior refuerzo mediante un colgajo pericraneal. Discusión: el abordaje endoscópico de los meningoencefaloceles nasales ha crecido notablemente en los últimos años debido a una tasa de éxito elevada tanto para la eliminación de dicha lesión, como para el adecuado control de la fístula de líquido cefalorraquídeo consecuente. Conclusiones: actualmente, la cirugía endoscópica nasosinusal es una herramienta muy útil para el tratamiento de patologías de base de cráneo y reduce la morbilidad causada por el abordaje transcraneal.

Introduction: Hurler syndrome is the most severe version of mucopolysaccharidosis I. The storage of dermatan and heparin sulfate in meninges allows the development of hydrocephalus and meningoencephaloceles. Case report: We report a 23-year-old female with this syndrome and a sinonasal encephalocele operated by endoscopic sinonasal surgery and subsequent pericranial flap as support. Discussion: Endoscopic sinonasal surgery has grown in last years in relation with treatment of sinonasal meningoencephaloceles due to a high rate of success removing the lesion and closing the subsequent cerebrospinal fluid fistula. Conclusion: Currently, the endoscopic sinonasal surgery has become a useful tool in the management of skull base pathologies, and reduces the morbidity due to a transcranial approach.

Case series of patients under biweekly treatment with laronidase: a report of a single center experience / Série de casos de pacientes em tratamento com laronidase quinzenal: relato da experiência de um centro

ABSTRACT Objective: To report the stabilization of urinary glycosaminoglicans (GAG) excretion and clinical improvements in patients with mucopolysaccharidosis type I (MPS I) under an alternative dose regimen of laronidase of 1.2 mg/kg every other week. Methods: We participated in a dose-optimization trial for laronidase in MPS-I patients using four alternative regimens: 0.58 mg/kg every week, 1.2 mg/kg every two weeks, 1.2 mg/kg every week and 1.8 mg/kg every other week (EOW). After the trial ended, the patients resumed the recommended dose and regimen of 0.58 mg/kg every week. Under this regimen, some patients presented difficulties in venous access and were unable to commute weekly to the treatment center. Therefore, we used an alternative regimen that consisted of 1.2 mg/kg EOW in eight patients. A retrospective study of medical records of MPS-I patients who underwent both enzyme replacement therapy (ERT) regimens, of 0.58 mg/kg every week and 1.2 mg/kg EOW, was done. Results: Patients remained clinically stable under the alternative regimen, did not present elevation of urinary GAG nor any adverse event. Conclusions: The switch of dose regimen to 1.2 mg/kg EOW of laronidase was safe, and did not cause any clinical worsening in patients who had been previously under standard dose ERT.

RESUMO Objetivo: Descrever a manutenção dos níveis de glicosaminoglicano (GAG) excretados na urina e da estabilização clínica em pacientes com mucopolissacaridose do tipo I (MPS I) com o uso da laronidase num regime de dose alternativo de 1,2 mg/kg a cada duas semanas. Método: Alguns pacientes do nosso serviço participaram de um estudo de otimização de dose da laronidase para o tratamento da MPS I no qual foram comparados quatro esquemas terapêuticos: 0,58 mg/kg/semana, 1,2 mg/kg a cada duas semanas, 1,2 mg/kg/semana e 1,8 mg/kg a cada duas semanas. Após o término do estudo, todos os pacientes passaram a receber a terapia de reposição enzimática (TRE) na dose padrão de bula, que é de 0,58 mg/kg/semana, e nesse regime alguns pais se queixaram da dificuldade em comparecer ao centro todas as semanas, além da dificuldade de se obter acesso para punção venosa. Com base nessas queixas, oito pacientes passaram a receber a TRE no regime alternativo de 1,2 mg/kg a cada duas semanas. Foi feito o estudo retrospectivo de dados de prontuário de pacientes com MPS I que fizeram TRE com laronidase nas doses 0,58 mg/kg/semana e 1,2 mg/kg a cada duas semanas. Resultados: Os pacientes mantiveram-se clinicamente estáveis, não apresentaram aumento dos níveis de GAG urinários nem eventos adversos durante o regime alternativo de dose. Conclusões: A mudança para o esquema de 1,2 mg/kg de laronidase a cada duas semanas foi segura e não acarretou piora clínica nos pacientes que já estavam em TRE na dose padrão.

Long-term restoration of alpha-L-iduronidase activity in fibroblasts from patients with mucopolysaccharidosis type I after non-viral gene transfer

Mucopolysaccharidosis type I (MPS I) is a lysosomal storage disorder caused by deficiency of alpha-L-iduronidase (IDUA). Limitations such as the need for weekly injections, high morbidity and mortality, and high cost of current treatments show that new approaches to treat this disease are required. In this study, we aimed to correct fibroblasts from a patient with MPS I using non-viral gene therapy. Using a plasmid encoding the human IDUA cDNA, we achieved stable high IDUA levels in transfected fibroblasts up to 6 months of treatment. These results serve as proof of concept that a non-viral approach can correct the enzyme deficiency in cells of patients with lysosomal storage disorders, which can be used as a research tool for a series of disease aspects. Future studies should focus on showing if this approach can be useful in small animals and clinical trials (AU)

Asociación de melanocitosis dérmica con enfermedades lisosomales / Association of dermal melanocytosis with lysosomal storage diseases

Introducción: la melanocitosis dérmica incluye un espectro de lesiones de piel que abarca la mancha mongólica, entre otras lesiones. Las enfermedades lisosomales son afecciones de base genética que se caracterizan por la acumulación de metabolitos insolubles parciamente degradados en los compartimentos lisosomales, debido a una determinada deficiencia enzimática. Las deficiencias de b-galactosidasa y de a-L-iduronidasa provocan la gangliosidosis GM1 y la mucopolisacaridosis tipo I respectivamente, ambas presentando similitudes en su presentación clínica. La asociación de la melanocitosis dérmica con las enfermedades lisosomales es poco común y mal entendida. Objetivo: reportar dos pacientes con esta rara asociación. Casos clínicos: dos varones de 3 y 9 meses sin antecedentes prenatales ni perinatales a destacar y antecedentes de infecciones respiratorias reiteradas. Se presentaron con retraso del desarrollo, hipotonía central y trastorno deglutorio. Al examen se constató hepatomegalia, fascies tosca y melanosis dérmica extensa. Los estudios permitieron diagnosticar al paciente de 3 meses mucopolisacaridosis Tipo I y al de 9 meses gangliosidosis GM1. Discusión: no se conoce exactamente la causa de esta asociación. Se plantea que sería el resultado de la acumulación de gangliósidos y heparán sulfato que estimularían al receptor del factor de crecimiento neuronal de tipo tirosinquinasa, deteniendo la migración de los melanocitos en la dermis. Por lo tanto la melanosis dérmica aberrante, en el contexto clínico adecuado, puede ser un signo que facilite el diagnóstico de una enfermedad lisosomal subyacente.

Introduction: dermal melanocytosis includes a spectrum of skin lesions, mongolian spots being one of them. Lysosomal storage diseases are characterized by the accumulation of partially degraded insoluble metabolites in lysosomal compartments due to enzyme deficiency. Deficiency in b-galactosidosisis is the cause of GM1 gangliosidosis and deficiency in a-L-iduronidasa of mucopolysaccharidosis type I. Both have similar clinical presentations. Association of dermal melanocytosis and lysosomal storage diseases is uncommon and misunderstood. Objective: to report the case of two patients with this rare association. Clinical cases: the study presents two boys, 3 and 9 months old, with no remarkable family, pregnancy or delivery history. Both had repeated respiratory tract infections. They presented with developmental delay, central hypotonia and swallowing disorder. Upon clinical examination they showed hepatomegaly, coarse facies and extensive dermal melanocytosis. They were diagnosed with GM1 gangliosidosis and mucopolysaccharidosis type I. Discussion: the cause of this association is not well known. It is hypothesized that accumulation of gangliosides and heparan sulfates stimulates tyrosine-kinase neuronal growth factor receptor, stopping dermal melanocytosis migration. Therefore extensive dermal melanocytosis, in an appropriate clinical setting, may contribute to diagnosing lysosomal storage diseases.

Neurological outcomes after hematopoietic stem cell transplantation for cerebral X-linked adrenoleukodystrophy, late onset metachromatic leukodystrophy and Hurler syndrome / Desfechos neurológicos após transplante de células tronco hematopoiéticas na adrenoleucodistrofia ligada ao X, forma cerebral, na leucodistrofia metacromática de início tardio e na síndrome de Hurler

ABSTRACT Hematopoietic stem cell transplantation (HSCT) is the only available treatment for the neurological involvement of disorders such as late-onset metachromatic leukodystrophy (MLD), mucopolysaccharidosis type I-Hurler (MPS-IH), and X-linked cerebral adrenoleukodystrophy (CALD). Objective To describe survival and neurological outcomes after HSCT for these disorders. Methods Seven CALD, 2 MLD and 2 MPS-IH patients underwent HSCT between 2007 and 2014. Neurological examinations, magnetic resonance imaging, molecular and biochemical studies were obtained at baseline and repeated when appropriated. Results Favorable outcomes were obtained with 4/5 related and 3/6 unrelated donors. Two patients died from procedure-related complications. Nine transplanted patients were alive after a median of 3.7 years: neurological stabilization was obtained in 5/6 CALD, 1/2 MLD, and one MPS-IH patient. Brain lesions of the MPS-IH patient were reduced four years after HSCT. Conclusion Good outcomes were obtained when HSCT was performed before adulthood, early in the clinical course, and/or from a related donor.

RESUMO O transplante de células tronco hematopoiéticas (TCTH) é o único tratamento disponível para o envolvimento neurológico de doenças como a leucodistrofia metacromática (MLD), a mucopolissacaridose tipo I-Hurler (MPS-IH) e a adrenoleucodistrofia (CALD). Objetivos Descrever a sobrevida e os desfechos neurológicos após o TCTH nessas doenças. Métodos Sete pacientes CALD, 2 MLD e 2 MPS-IH realizaram TCTH entre 2007 e 2014. Avaliações neurológicas, ressonância nuclear magnética e estudos bioquímicos e moleculares foram feitos no baseline e repetidos quando apropriado. Resultados Desfechos favoráveis foram obtidos em 4/5 TCTH de doadores relacionados e em 3/6 não relacionados. Dois pacientes faleceram de complicações do procedimento. Nove transplantados sobreviveram após uma mediana de 3,7 anos: estabilização neurológica foi obtida em 5/6 CALD, ½ MLD e em um caso MPS-IH. As lesões encefálicas de um caso MPS-IH reduziram-se quatro anos após o TCTH. Conclusão Bons desfechos foram obtidos quando o TCTH foi feito antes da vida adulta, cedo no curso clínico e/ou a partir de um doador relacionado.

The impact of laronidase treatment in otolaryngological manifestations of patients with mucopolysaccharidosis / Impacto do tratamento com laronidase nas manifestações otorrinolaringológicas de pacientes com mucopolissacaridose

ABSTRACT INTRODUCTION: Mucopolysaccharidosis (MPS) is a lysosomal storage disease caused by deficiency of a-l-iduronidase. The otolaryngological findings include hearing loss, otorrhea, recurrent otitis, hypertrophy of tonsils and adenoid, recurrent rhinosinusitis, speech disorders, snoring, oral breathing and nasal obstruction. OBJECTIVE: To evaluate the impact of enzymatic replacement therapy with laronidase (Aldurazyme(r)) in patients with mucopolysaccharidosis (MPS I), regarding sleep and hearing disorders, and clinical manifestations in the upper respiratory tract (URT). METHODS: Nine patients with MPS I (8 Hurler-Scheie, and 1 Scheie phenotypes) of both sexes, ages ranging between 3 and 20 years, were included in this study. Patients were evaluated between seven and 11 months before the treatment and between 16 and 22 months after the onset of the enzymatic replacement. They were all submitted to a clinical and otolaryngological evaluation, including nasofibroscopical, polysomnographic and audiologic exams. RESULTS: The results' data showed decreasing of the frequency of ear, nose and throat infections, with improvement of the rhinorrhea and respiratory quality. No remarkable changes were observed regarding macroglossia and tonsil and adenoid hypertrophy. Audiometric and polysomnographic evaluations did not show statistical significance. CONCLUSION: Enzymatic replacement therapy in patients with mucopolysaccharidosis I provides control of recurrent URT infections, rhinorrhea and respiratory quality, however it is does not seem to improve audiologic and polisomnographic parameters, with no effect on adenoid and tonsils hypertrophy and macroglossia.

Resumo Introdução: Mucopolissacaridose (MPS) é uma doença de depósito lisossômico causada pela deficiência de a-l-iduronidase. Os achados otorrinolaringológicos incluem perda auditiva, otorreia, otites de repetição, hipertrofia adenotonsilar, rinossinusite recorrente, distúrbios da fala, roncos, respiração bucal e obstrução nasal. Objetivo: Avaliar o impacto da terapia de reposição enzimática com laronidase (Aldurazyme(r)) em pacientes com mucopolissacaridose I (MPS I) em relação ao sono, distúrbios auditivos e manifestações clínicas do trato respiratório superior (TRS). Método: Nove pacientes com MPS I (oito com fenótipo Hurler-Scheie e um com fenótipo Scheie), de ambos os sexos, com idades variando entre 3 e 20 anos, foram incluídos neste estudo. Os pacientes foram avaliados entre 7 e 11 meses antes do tratamento e entre 16 e 22 meses após o início da substituição enzimática. Todos foram submetidos a uma avaliação clínica e otorrinolaringológica, incluindo nasofibroscopia, polissonografia e exames radiológicos. Resultados: Os dados dos resultados mostraram diminuição da frequência de infecções de orelha, nariz e garganta, com melhora da rinorreia e da qualidade respiratória. Mudanças significativas não foram observadas em relação à macroglossia e à hipertrofia adenotonsilar. Avaliações audiométricas e polissonográficas não apresentaram significância estatística. Conclusão: A terapia de reposição enzimática em pacientes com mucopolissacaridose I fornece controle de infecções recorrentes do TRS, rinorreia e qualidade respiratória, porém, não parece melhorar os parâmetros audiológicos e polissonográficos, ou exercer efeito sobre a hipertrofia adenotonsilar e macroglossia.

Tratamiento de mucopolisacaridosis tipo I con trasplante de células madre de sangre de cordón umbilical de donante no emparentado: informe del primer caso exitoso en Colombia / Treatment of mucopolysaccharidosis I with cord blood stem cell transplantation of unrelated donor: report of first successful case in Colombia

Resumen: se presenta el primer caso exitoso en Colombia de trasplante de células madre de sangre de cordón umbilical no relacionadas, en un niño de 30 meses de edad con diagnóstico de mucopolisacaridosis tipo I. El paciente fue recibido a los seis meses de edad por presentar signos y síntomas típicos de la enfermedad, por lo que se realizó confirmación diagnóstica por bioquímica y se determinó la mutación genética. Se inició terapia de reemplazo enzimático con laronidasa a los 13 meses de edad y se llevó a cabo un trasplante de sangre de cordón umbilical de un donante no emparentado a los 30 meses, alcanzando una sobrevida superior a los tres años con mejoría en el neurodesarrollo y cambios fenotípicos marcados, sin evidencia de cifosis, macrocefalia y macroglosia, entre otros. El control ecocardiográfico actual es normal, sin manejo farmacológico, evidencia de cifosis, macrocefalia o macroglosia. Como se reporta en la literatura, el trasplante de células madre de sangre de cordón umbilical de donante no emparentado es una alternativa efectiva y segura en el tratamiento de esta enfermedad.

Abstract: here we present the first successful case in Colombia of transplantation of unrelated cord blood stem cell transplantation in a 30-month-old boy diagnosed with mucopolysaccharidosis type I. Patient was received at the age of six months showing typical signs and symptoms of the disease. Biochemical diagnosis was confirmed and the genetic mutation was determined. Patient began enzymereplacement therapy with laronidase at the age of 13 months and, at the age of 30 months he underwent cord blood stem cell transplantation. The boy reaching more than three years of survival with neurologic progression with marked phenotypic changes, decrease of coarse facies, active, walking without help, with normal echocardiography results without medication, no evidence of kyphosis, macrocephaly and macroglossia. In this case, it is evident that transplantation of unrelated hematopoietic stem cells from cord blood is an effective and safe alternative in treating Hurler syndrome.

A Simple and Rapid Method Based on Liquid Chromatography-Tandem Mass Spectrometry for the Measurement of alpha-L-Iduronidase Activity in Dried Blood Spots: An Application to Mucopolysaccharidosis I (Hurler) Screening

BACKGROUND: We developed an analytical method to measure alpha-L-iduronidase (IDUA) activity in dried blood spots. This was achieved by using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with electrospray ionization in the positive ion mode. METHODS: Chromatographic separation was completed using mobile phase involving water-formic acid and acetonitrile-formic acid over 2.8 min of run time on a column with a Kinetex XB-C18 (Phenomenex, USA). The detection of column effluent was performed using a Xevo TQ-S triple quadrupole mass spectrometer (Waters, USA) in the multiple-reaction monitoring mode. This method was verified with blank and control samples at four activity levels: base, low, medium, and high. Control materials were provided from Centers for Disease Control and Prevention (CDC). RESULTS: Intra- and inter-day precisions were between 2.6% and 16.5% and between 7.9% and 17.0%, respectively. A correlative regression study on the IDUA activity in CDC-control samples performed to assess the validity of the developed method showed a highly significant linear association (r2=0.9976) between the calculated and CDC-reported values and an obvious difference in activity among the four levels. This reliable analytical method was applied to mucopolysaccharidosis I (Hurler) screening of patients under treatment (n=4) and in normal controls (n=129). IDUA activity ranged from 8.98 to 77.12 micromol/hr/L) in normal controls, and patients undergoing medical treatment showed low IDUA activity. CONCLUSIONS: This method had advantages of simplicity, rapid sample preparation, and liquid chromatographic separation, which efficiently inhibited ionization suppression induced by matrix effects in mass spectrometric detection.

Evolução motora de paciente com mucopolissacaridose tipo 1 / Motor outcome in a patient with mucopolysaccharidosis type 1

OBJETIVO: Relatar os aspectos funcionais de uma criança com mucopolissacaridose tipo 1, descrevendo suas principais alterações após breve tratamento fisioterapêutico. DESCRIÇÃO DE CASO: Criança com 34 meses, portadora de mucopolissacaridose tipo 1 iniciou tratamento fisioterapêutico, duas vezes por semana, durante 50 minutos, sendo avaliada mensalmente por meio das atividades propostas pela Escala de Desenvolvimento Motor (EDM), que analisa a motricidade fina e global, o equilíbrio, o esquema corporal e a organização temporal e espacial. Na primeira avaliação, a criança apresentava-se com 34 meses de idade cronológica e 18 meses de idade motora geral, com melhor pontuação no item organização espacial, segundo a EDM. Após quatro meses, a idade motora geral era de 20 meses; porém, houve melhora da motricidade global. COMETÁRIOS: A análise das atividades funcionais do paciente relatado demonstrou atraso no desenvolvimento motor. A intervenção terapêutica possibilitou evolução favorável, principalmente na motricidade global, mesmo tratando-se de um portador de doença evolutiva.

OBJECTIVE: To report the functional aspects of a child with mucopolysaccharidosis type 1 and to describe its main dysfunctions after a brief physiotherapy intervention. CASE DESCRIPTION: A 34 months old child with mucopolysaccharidosis type 1 started a physiotherapy treatment twice a week (50 minutes each session). Her motor skills were monthly evaluated by the Motor Development Scale (MDS), which analyzes fine and global motor skills, balance, body schema and temporal and spatial organization. In the first evaluation, the child had 34 months of chronological age and 18 months of global motor age, with better performance in spacial organization, according to MDS. After four months, the child had 20 months of general motor age; however, the global motor skills improved. Comments: The analysis of the patient's functional activities showed motor delay. The therapeutic intervention allowed favorable outcome, mainly in the global motor skills, even considering the presence of a progressive disease.

Terapia de reposição enzimática para as mucopolissacaridoses I, II e VI: recomendações de um grupo de especialistas brasileiros / Enzyme replacement therapy for mucopolysaccharidoses I, II and VI: recommendations from a group of Brazilian F experts

As mucopolissacaridoses (MPS) são doenças genéticas raras causadas pela deficiência de enzimas lisossômicas específicas que afetam o catabolismo de glicosaminoglicanos (GAG). O acúmulo de GAG em vários órgãos e tecidos nos pacientes afetados pelas MPS resulta em uma série de sinais e sintomas, integrantes de um quadro clínico multissistêmico que compromete ossos e articulações, vias respiratórias, sistema cardiovascular e muitos outros órgãos e tecidos, incluindo, em alguns casos, as funções cognitivas. Já foram identificados 11 defeitos enzimáticos que causam sete tipos diferentes de MPS. Antes do advento de terapias dirigidas para a restauração da atividade da enzima deficiente, o tratamento das MPS tinha como principal foco a prevenção e o cuidado das complicações, aspecto ainda bastante importante no manejo desses pacientes. Na década de 80 foi proposto o tratamento das MPS com transplante de medula óssea/transplante de células tronco hematopoiéticas (TMO/TCTH) e na década de 90 começou o desenvolvimento da Terapia de Reposição Enzimática (TRE), que se tornou uma realidade aprovada para uso clínico nas MPS I, II e VI na primeira década do século 21. Os autores deste trabalho têm a convicção de que um melhor futuro para os pacientes afetados pelas MPS depende da identificação, compreensão e manejo adequado das manifestações multissistêmicas dessas doenças, incluindo medidas de suporte (que devem fazer parte da assistência multidisciplinar regular destes pacientes) e terapias específicas...

Mucopolysaccharidoses (MPS) are rare genetic diseases caused by deficiency of specific lysosomal enzymes that affect catabolism of glycosaminoglycans (GAG). Accumulation of GAG in various organs and tissues in MPS patients results in a series of signs and symptoms, producing a multisystemic condition affecting bones and joints, the respiratory and cardiovascular systems and many other organs and tissues, including in some cases, cognitive performance. So far, eleven enzyme defects that cause seven different types of MPS have been identified. Before introduction of therapies to restore deficient enzyme activity, treatment of MPS focused primnarily on prevention and care of complications, still a very important aspect in the management of these patients. In the 80's treatment of MPS with bone marrow transplantation/hematopoietic stem cells transplantation (BMT/HSCT) was proposed and in the 90's, enzyme replacement therapy (ERT),began to be developed and was approved for clinical use in MPS I, II and VI in the first decade of the 21st century. The authors of this paper are convinced that a better future for patients affected by mucopolysaccharidoses depends upon identifying, understanding and appropriately managing the multisystemic manifestations of these diseases. This includes the provision of support measures (which should be part of regular multidisciplinary care of these patients) and of specific therapies...

Identification of mutation in the ?-L-iduronidase gene (IDUA) in Hurler syndromes in Chinese populations / 中国病理生理杂志

AIM: To investigate the mutation type in the IDUA gene of Liaoning district mucopolysaccharidosis I (MPS-I) patients. METHODS: The mutation type and polymorphism site in the IDUA gene of Liaoning district MPS-I patients were detected by PCR-RFLP, SSCP and DNA sequencing. RESULTS: ① There is a new mutation (1278-g-a) in the IDUA gene of Liaoning district MPS-I patients. ② There is no the common mutation (W402X and Q70X) of European patients and the common mutation (R89Q) of Japanese patients in the 10 families we studied. CONCLUSION: The mutation type in the IDUA gene of Liaoning district MPS-I patients is different from that of other countries and districts.

The mutation of ?-L-iduronidase gene for mucopolysaccharidosis type I in Liaoning district populations / 中国病理生理杂志

AIM: To investigate the mutatation type and polymorphism site in the ?-L-iduronidase (IDUA) gene of Liaoning district MPS-I patients. METHODS: The mutation type and polymorphism site in the IDUA gene of Liaoning district mucopolysaccharidosis type I (MPS-I) patients were detected by PCR-SSCP and DNA sequencing. RESULTS: ① 2 new mutations: R363H, 880+g-c in the IDUA gene of Liaoning district MPS-I patients were found. ② There were 3 polymorphism sites: R105Q、L118 and A361T in the IDUA gene of Liaoning district MPS-I patients. CONCLUSIONS: The mutation type in the IDUA gene of Liaoning district MPS-I patients is different from that of other countries and districts, while the polymorphism site in the IDUA gene of Liaoning district MPS-I patients is the same as that of other countries. [