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BACKGROUND: Current clinical diagnosis pathway for lysosomal storage disorders (LSDs) involves sequential biochemical enzymatic tests followed by DNA sequencing, which is iterative, has low diagnostic yield and is costly due to overlapping clinical presentations. Here, we describe a novel low-cost and high-throughput sequencing assay using single-molecule molecular inversion probes (smMIPs) to screen for causative single nucleotide variants (SNVs) and copy number variants (CNVs) in genes associated with 29 common LSDs in India. RESULTS: 903 smMIPs were designed to target exon and exon-intron boundaries of targeted genes (n = 23; 53.7 kb of the human genome) and were equimolarly pooled to create a sequencing library. After extensive validation in a cohort of 50 patients, we screened 300 patients with either biochemical diagnosis (n = 187) or clinical suspicion (n = 113) of LSDs. A diagnostic yield of 83.4% was observed in patients with prior biochemical diagnosis of LSD. Furthermore, diagnostic yield of 73.9% (n = 54/73) was observed in patients with high clinical suspicion of LSD in contrast with 2.4% (n = 1/40) in patients with low clinical suspicion of LSD. In addition to detecting SNVs, the assay could detect single and multi-exon copy number variants with high confidence. Critically, Niemann-Pick disease type C and neuronal ceroid lipofuscinosis-6 diseases for which biochemical testing is unavailable, could be diagnosed using our assay. Lastly, we observed a non-inferior performance of the assay in DNA extracted from dried blood spots in comparison with whole blood. CONCLUSION: We developed a flexible and scalable assay to reliably detect genetic causes of 29 common LSDs in India. The assay consolidates the detection of multiple variant types in multiple sample types while having improved diagnostic yield at same or lower cost compared to current clinical paradigm.
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Variaciones en el Número de Copia de ADN , Pruebas Genéticas , Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedades por Almacenamiento Lisosomal , Humanos , Enfermedades por Almacenamiento Lisosomal/genética , Enfermedades por Almacenamiento Lisosomal/diagnóstico , India , Variaciones en el Número de Copia de ADN/genética , Pruebas Genéticas/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Polimorfismo de Nucleótido Simple/genética , Femenino , Masculino , Sondas Moleculares/genéticaRESUMEN
CHST3-related chondrodysplasia with congenital joint dislocations (CDCJD, #MIM 143095), is a rare genetic skeletal disorder caused by biallelic loss of function variants in CHST3. CHST3 is critical for the sulfation of chondroitin sulfate. This study delineates the clinical presentation of nine individuals featuring the key symptoms of CDCJD; congenital joint (knee and elbow) dislocations, short trunk short stature progressive vertebral anomalies, and metacarpal shortening. Additional manifestations include irregular distal femoral epiphysis, supernumerary carpal ossification centers, bifid humerus, club foot, and cardiac abnormalities. Sanger sequencing was carried out to investigate molecular etiology in eight patients and exome sequencing in one. Genetic testing revealed five homozygous variants in CHST3 (four were novel and one was previously reported). All these variants are located on sulfotransferase domain of CHST3 protein and were classified as pathogenic/ likely pathogenic. We thus report on nine individuals with CHST3-related chondrodysplasia with congenital joint dislocations from India and suggest monitoring the health of cardiac valves in this condition.
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Enanismo , Luxaciones Articulares , Anomalías Musculoesqueléticas , Osteocondrodisplasias , Humanos , Luxaciones Articulares/diagnóstico , Luxaciones Articulares/genética , Mutación , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/genética , Sulfotransferasas/genéticaRESUMEN
Background Treating beta-thalassaemia major may entail high costs with considerable out-of-pocket expenditure. Therefore, determination and valuation of the economic costs of a common haemoglobinopathy such as beta-thalassaemia major in India may provide insights to evolve policies for reduction or elimination of the disease. We estimated economic burden of beta-thalassaemia major in Mumbai in terms of cost to the family and the healthcare system. Methods This single-centre, prospective, cross-sectional, non-interventional study included children <12 years of age treated at the thalassaemia day care centre of a public hospital in Mumbai. The demographic data and treatment-related information was recorded. Cost of illness was studied from a societal perspective by the prevalence-based approach. Direct (medical and non-medical), indirect (loss of wages and loss of school days) and intangible costs (closed-ended iterative bidding) were calculated for each patient by interview. Results The total annual cost of treating 130 children with beta-thalassaemia major in Mumbai was â¹86 72 412 (US$ 127 535) or â¹66 710 (US$ 981) per patient per year and â¹12 82 30 412 (US$ 1 885 741) including intangible costs. Direct costs contributed to 94% of the cost of illness with chelation therapy (23%) and blood investigations (21%) being major contributors. Direct and indirect costs correlated significantly with duration of blood transfusion (p<0.05 and p=0.006, respectively), whereas indirect costs correlated with socioeconomic status (rho=0.25). Conclusion The majority (94%) of costs incurred by families for treatment of beta-thalassaemia major are direct costs, especially expenses for chelation and blood investigations. Even at subsidized rates, financial burden to the families from lower socioeconomic strata is likely to be considerable as these are out-of-pocket expenses. In consideration of the economic impact of treating beta-thalassaemia major in individual families, the healthcare system and society, it is prudent to promote and pursue long-term and short-term measures with urgent emphasis on prevention as a public health activity at the national level in India.
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Estrés Financiero , Talasemia beta , Niño , Humanos , Talasemia beta/epidemiología , Talasemia beta/terapia , Estudios Transversales , Estudios Prospectivos , Costo de Enfermedad , Hospitales PúblicosRESUMEN
Pseudoachondroplasia (PSACH) is an autosomal dominant disorder characterized by rhizomelic short-limbed skeletal dysplasia. The primary clinical and radiographic features include disproportionate dwarfism, joint laxity and hyperextensibility, exaggerated lumbar lordosis, and late ossification of the epiphyses. Identification of disease-causing variants in heterozygous state in COMP establishes the molecular diagnosis of PSACH. We examined 11 families with clinical features suggestive of PSACH. In nine families, we used Sanger sequencing of exons 8-19 of COMP (NM_000095.2) and in two families exome sequencing was used for confirming the diagnosis. We identified 10 de novo variants, including five known variants (c.925G>A, c.976G>A, c.1201G>T, c.1417_1419del, and c.1511G>A) and five variants (c.874T>C, c.1201G>C, c.1309G>A, c.1416_1421delCGACAA, and c.1445A>T) which are not reported outside Indian ethnicity. We hereby report the largest series of individuals with molecular diagnosis of PSACH from India and reiterate the well-known genotype-phenotype corelation in PSACH.
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Acondroplasia , Acondroplasia/diagnóstico , Acondroplasia/genética , Proteína de la Matriz Oligomérica del Cartílago/genética , Proteínas de la Matriz Extracelular/genética , Genotipo , Humanos , Proteínas Matrilinas/genética , Mutación , FenotipoRESUMEN
Pathogenic variations in SMPD1 lead to acid sphingomyelinase deficiency (ASMD), that is, Niemann-Pick disease (NPD) type A and B (NPA, NPB), which is a recessive lysosomal storage disease. The knowledge of variant spectrum in Indian patients is crucial for early and accurate NPD diagnosis and genetic counseling of families. In this study, we recruited 40 unrelated pediatric patients manifesting symptoms of ASMD and subnormal ASM enzyme activity. Variations in SMPD1 were studied using Sanger sequencing for all exons, followed by interpretation of variants based on American College of Medical Genetics and Genomics & Association for Molecular Pathology (ACMG/AMP) criteria. We identified 18 previously unreported variants and 21 known variants, including missense, nonsense, deletions, duplications, and splice site variations with disease-causing potential. Eight missense variants were functionally characterized using in silico molecular dynamic simulation and in vitro transient transfection in HEK293T cells, followed by ASM enzyme assay, immunoblot, and immunofluorescence studies. All the variants showed reduced ASM activity in transfected cells confirming their disease-causing potential. The study provides data for efficient prenatal diagnosis and genetic counseling of families with NPD type A and B.
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Enfermedad de Niemann-Pick Tipo A , Enfermedades de Niemann-Pick , Esfingomielina Fosfodiesterasa/genética , Niño , Exones , Femenino , Células HEK293 , Humanos , Mutación , Enfermedad de Niemann-Pick Tipo A/genética , Enfermedad de Niemann-Pick Tipo A/patología , Enfermedades de Niemann-Pick/diagnóstico , Enfermedades de Niemann-Pick/genética , EmbarazoRESUMEN
Genetic disorders with predominant central nervous system white matter abnormalities (CNS WMAs), also called leukodystrophies, are heterogeneous entities. We ascertained 117 individuals with CNS WMAs from 104 unrelated families. Targeted genetic testing was carried out in 16 families and 13 of them received a diagnosis. Chromosomal microarray (CMA) was performed for three families and one received a diagnosis. Mendeliome sequencing was used for testing 11 families and all received a diagnosis. Whole exome sequencing (WES) was performed in 80 families and was diagnostic in 52 (65%). Singleton WES was diagnostic for 50/75 (66.67%) families. Overall, genetic diagnoses were obtained in 77 families (74.03%). Twenty-two of 47 distinct disorders observed in this cohort have not been reported in Indian individuals previously. Notably, disorders of nuclear mitochondrial pathology were most frequent (9 disorders in 20 families). Thirty-seven of 75 (49.33%) disease-causing variants are novel. To sum up, the present cohort describes the phenotypic and genotypic spectrum of genetic disorders with CNS WMAs in our population. It demonstrates WES, especially singleton WES, as an efficient tool in the diagnosis of these heterogeneous entities. It also highlights possible founder events and recurrent disease-causing variants in our population and their implications on the testing strategy.
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Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Malformaciones del Sistema Nervioso/diagnóstico , Malformaciones del Sistema Nervioso/genética , Sustancia Blanca/anomalías , Alelos , Aberraciones Cromosómicas , Consanguinidad , Familia , Estudios de Asociación Genética/métodos , Pruebas Genéticas , Humanos , India/epidemiología , Análisis por Micromatrices , Mutación , Malformaciones del Sistema Nervioso/epidemiología , Secuenciación del ExomaRESUMEN
OBJECTIVES: To evaluate the clinical and molecular spectrum, and factors affecting clinical outcome of patients in India diagnosed with infantile-onset Pompe disease (IOPD). STUDY DESIGN: In this multicenter, cross-sectional study, we evaluated the records of 77 patients with IOPD to analyze their clinical course, outcomes, and factors influencing the outcomes. RESULTS: Of the 77 patients with IOPD, phenotype data were available in 59; 46 (78%) had the classic phenotype. Overall, 58 of 77 (75%) and 19 of 77 (25%) patients were symptomatic before and after age 6 months, respectively. Alpha-glucosidase gene variant analysis available for 48 patients (96 alleles) showed missense variants in 49 alleles. Cross-reactive immunologic material (CRIM) status could be determined or predicted in 44 of 48 patients. In total, 32 of 44 patients (72%) were CRIM-positive, and 12 of 44 patients (27%) were CRIM-negative. Thirty-nine cases received enzyme-replacement therapy (ERT), alglucosidase alfa, and 38 patients never received ERT. Median age at initiation of ERT was 6.5 months. Response to ERT was better in babies who had CRIM-positive, non-classic IOPD. CONCLUSIONS: This study highlights the clinical spectrum of IOPD in India and provides an insight on various factors, such as undernutrition, feeding difficulties, and recurrent respiratory infection, as possible factors influencing clinical outcomes in these patients. The study also reiterates the importance of raising awareness among clinicians about the need for early diagnosis and timely treatment of IOPD.
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Enfermedad del Almacenamiento de Glucógeno Tipo II/genética , Enfermedad del Almacenamiento de Glucógeno Tipo II/fisiopatología , Edad de Inicio , Estudios Transversales , Femenino , Enfermedad del Almacenamiento de Glucógeno Tipo II/mortalidad , Enfermedad del Almacenamiento de Glucógeno Tipo II/terapia , Humanos , India/epidemiología , Lactante , Recién Nacido , Masculino , Fenotipo , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Spondyloepimetaphyseal dysplasias (SEMD) are a group of genetically heterogeneous skeletal disorders characterized by abnormal vertebral bodies and epimetaphyseal abnormalities. We investigated two families with a new SEMD type with one proband each. They showed mild facial dysmorphism, flat vertebral bodies (platyspondyly), large epiphyses, metaphyseal dysplasia, and hallux valgus as common clinical features. By trio-exome sequencing, the homozygous missense variant c.797G>A/p.(Cys266Tyr) in PISD was found in both affected individuals. Based on exome data analyses for homozygous regions, the two patients shared a single homozygous block on chromosome 22 including PISD, indicating their remote consanguinity. PISD encodes phosphatidylserine (PS) decarboxylase that is localized in the inner mitochondrial membrane and catalyzes the decarboxylation of PS to phosphatidylethanolamine (PE) in mammalian cells. PE occurs at high abundance in mitochondrial membranes. Patient-derived fibroblasts showed fragmented mitochondrial morphology. Treatment of patient cells with MG-132 or staurosporine to induce activation of the intrinsic apoptosis pathway revealed significantly decreased cell viability with increased caspase-3 and caspase-7 activation. Remarkably, ethanolamine (Etn) supplementation largely restored cell viability and enhanced apoptosis in MG-132-stressed patient cells. Our data demonstrate that the biallelic hypomorphic PISD variant p.(Cys266Tyr) is associated with a novel SEMD form, which may be treatable with Etn administration.
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Carboxiliasas/genética , Epífisis/anomalías , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Mitocondrias/metabolismo , Mutación/genética , Osteocondrodisplasias/genética , Apoptosis , Caspasa 3/metabolismo , Caspasa 7/metabolismo , Supervivencia Celular , Células Cultivadas , Niño , Preescolar , Etanolamina/farmacología , Femenino , Fibroblastos/patología , Homocigoto , Humanos , Lactante , Recién Nacido , Leupeptinas/farmacología , Masculino , Mutación Missense/genética , Linaje , Secuenciación del ExomaRESUMEN
BACKGROUND: Gaucher disease is a rare pan-ethnic, lysosomal storage disorder resulting due to beta-Glucosidase (GBA1) gene defect. This leads to the glucocerebrosidase enzyme deficiency and an increased accumulation of undegraded glycolipid glucocerebroside inside the cells' lysosomes. To date, nearly 460 mutations have been described in the GBA1 gene. With the aim to determine mutations spectrum and molecular pathology of Gaucher disease in India, the present study investigated one hundred unrelated patients (age range: 1 day to 31 years) having splenomegaly, with or without hepatomegaly, cytopenia and bone abnormality in some of the patients. METHODS: The biochemical investigation for the plasma chitotriosidase enzyme activity and ß-Glucosidase enzyme activity confirmed the Gaucher disease. The mutations were identified by screening the patients' whole GBA gene coding region using bidirectional Sanger sequencing. RESULTS: The biochemical analysis revealed a significant reduction in the ß-Glucosidase activity in all patients. Sanger sequencing established 71 patients with homozygous mutation and 22 patients with compound heterozygous mutation in GBA1 gene. Lack of identification of mutations in three patients suggests the possibility of either large deletion/duplication or deep intronic variations in the GBA1 gene. In four cases, where the proband died due to confirmed Gaucher disease, the parents were found to be a carrier. Overall, the study identified 33 mutations in 100 patients that also covers four missense mutations (p.Ser136Leu, p.Leu279Val, p.Gly383Asp, p.Gly399Arg) not previously reported in Gaucher disease patients. The mutation p.Leu483Pro was identified as the most commonly occurring Gaucher disease mutation in the study (62% patients). The second common mutations identified were p.Arg535Cys (7% patients) and RecNcil (7% patients). Another complex mutation Complex C was identified in a compound heterozygous status (3% patients). The homology modeling of the novel mutations suggested the destabilization of the GBA protein structure due to conformational changes. CONCLUSIONS: The study reports four novel and 29 known mutations identified in the GBA1 gene in one-hundred Gaucher patients. The given study establishes p.Leu483Pro as the most prevalent mutation in the Indian patients with type 1 Gaucher disease that provide new insight into the molecular basis of Gaucher Disease in India.
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Enfermedad de Gaucher/genética , Glucosilceramidasa/genética , Mutación , Análisis de Secuencia de ADN/métodos , Población Blanca/genética , Adolescente , Adulto , Sustitución de Aminoácidos , Niño , Preescolar , Exones , Femenino , Enfermedad de Gaucher/metabolismo , Glucosilceramidasa/química , Glucosilceramidasa/metabolismo , Humanos , India , Lactante , Recién Nacido , Masculino , Modelos Moleculares , Homología Estructural de Proteína , Adulto JovenRESUMEN
Aicardi-Goutières syndrome is an early-onset severe neurological disorder characterized by intracranial calcification, white matter abnormalities, hepatosplenomegaly, cerebrospinal fluid lymphocytosis, and elevated interferon-α levels, thus mimicking congenital viral infections. It is a genetically heterogeneous condition and autosomal recessive and autosomal dominant forms with variations in seven genes known till date. Variations in RNASEH2C cause an autosomal recessive form of AGS. Here we report three Indian families with variant, c.205C>T (NM_032193.3, p.Arg69Trp) in RNASEH2C gene identified by whole-exome sequencing and targeted molecular testing of the variant. Review of literature and our data suggest this is likely to be a founder variant in Asians and it would be a good initial variant to screen in patients with Aicardi-Goutières syndrome in Indians.
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Alelos , Enfermedades Autoinmunes del Sistema Nervioso/diagnóstico , Enfermedades Autoinmunes del Sistema Nervioso/genética , Efecto Fundador , Mutación , Malformaciones del Sistema Nervioso/diagnóstico , Malformaciones del Sistema Nervioso/genética , Ribonucleasa H/genética , Sustitución de Aminoácidos , Encéfalo/anomalías , Encéfalo/diagnóstico por imagen , Mapeo Cromosómico , Consanguinidad , Femenino , Estudios de Asociación Genética , Homocigoto , Humanos , India , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Linaje , Fenotipo , Secuenciación del ExomaRESUMEN
BACKGROUND: Niemann-Pick disease type C (NPC) is an inherited metabolic disorder; due to defect in cellular cholesterol trafficking. It is clinically a heterogeneous disease with variable age of onset with multiple organ systems being involved. NPC1 gene is involved in 95% cases where as remaining ~5% cases are linked with NPC2 gene. CASE PRESENTATION: Case-1, a 14-months-old female presented with recurrent respiratory distress, failure to thrive and hepatosplenomegaly. Lung biopsy was suggestive of alveolar proteinosis and liver biopsy confirmed foamy macrophages. Molecular analysis revealed homozygous mutation c.141C > A in exon 2 of NPC2 gene. Case-2, a 3-year-old male presented with dyspnoea and hepatomegaly noticed at 1 year of age. HRCT-scan of thoracic region showed consolidation with mediastinal lymphadenopathy. Broncho-alveolar lavage revealed moderate amount of foamy macrophages and bone marrow examination detected foam cells. Homozygous T > C transition in intron 1 of the NPC2 gene was identified. CONCLUSION: Our study demonstrates that NPC2 can present in early years of life with pulmonary complications like alveolar proteinosis and hepatosplenomegaly or hepatomegaly due to mutation in NPC2 gene. An early suspicion will help clinicians to clinch its diagnosis, management and genetic counselling.
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Proteínas Portadoras/genética , Glicoproteínas/genética , Enfermedades Pulmonares/etiología , Mutación , Enfermedad de Niemann-Pick Tipo C/genética , Edad de Inicio , Preescolar , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Humanos , Lactante , Masculino , Proteínas de Transporte VesicularRESUMEN
BACKGROUND & OBJECTIVES: Mucopolysaccharidosis type VI (MPS VI) is a rare, autosomal recessive lysosomal storage disorder caused by deficient enzymatic activity of N-acetyl galactosamine-4-sulphatase resulting from mutations in the arylsulphatase B (ARSB) gene. The ARSB gene is located on chromosome 5q11-q13 and is composed of eight exons. More than hundred ARSB mutations have been reported so far, but the mutation spectrum of MPS VI in India is still unknown. Hence, the aim of the present study was to identify the mutational spectrum in patients with MPS VI in India and to study the genotype-phenotype association and functional outcomes of these mutations. METHODS: Molecular characterization of the ARSB gene by Sanger sequencing was done for 15 patients (aged 15 months to 11 yr) who were enzymatically confirmed to have MPS VI. Age of onset, clinical progression and enzyme activity levels in each patient were studied to look for genotype-phenotype association. Haplotype analysis performed for unrelated patients with the recurring mutation W450C, was suggestive of a founder effect. Sequence and structural analyses of the ARSB protein using standard software were carried out to determine the impact of detected mutations on the function of the ARSB protein. RESULTS: A total of 12 mutations were identified, of which nine were novel mutations namely, p.D53N, p.L98R, p.Y103SfsX9, p.W353X, p.H393R, p.F166fsX18, p.I220fsX5, p.W450L, and p.W450C, and three were known mutations (p.D54N, p.A237D and p.S320R). The nine novel sequence variants were confirmed not to be polymorphic variants by performing sequencing in 50 unaffected individuals from the same ethnic population. INTERPRETATION & CONCLUSIONS: Nine novel mutations were identified in MPS VI cases from India in the present study. The study also provides some insights into the genotype-phenotype association in MPS VI.
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Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Mucopolisacaridosis VI/genética , N-Acetilgalactosamina-4-Sulfatasa/genética , Niño , Preescolar , Exones/genética , Femenino , Haplotipos , Humanos , India , Lactante , Masculino , Mucopolisacaridosis VI/patología , MutaciónRESUMEN
Phenylketonuria (PKU) is an autosomal recessive metabolic disorder caused by mutational inactivation of the phenylalanine hydroxylase (PAH) gene. Missense mutations are the most common PAH mutation type detected in PKU patients worldwide. We performed PAH mutation analysis in 27 suspected Indian PKU families (including 7 from our previous study) followed by structure and function analysis of specific missense and splice/insertion-deletion/nonsense mutations, respectively. Of the 27 families, disease-causing mutations were detected in 25. A total of 20 different mutations were identified of which 7 "unique" mutations accounted for 13 of 25 mutation positive families. The unique mutations detected exclusively in Indian PKU patients included three recurrent mutations detected in three families each. The 20 mutations included only 5 missense mutations in addition to 5 splice, 4 each nonsense and insertion-deletion mutations, a silent variant in coding region and a 3'UTR mutation. One deletion and two nonsense mutations were characterized to confirm significant reduction in mutant transcript levels possibly through activation of nonsense mediated decay. All missense mutations affected conserved amino acid residues and sequence and structure analysis suggested significant perturbations in the enzyme activity of respective mutant proteins. This is probably the first report of identification of a significantly low proportion of missense PAH mutations from PKU families and together with the presence of a high proportion of splice, insertion-deletion, and nonsense mutations, points to a unique PAH mutation profile in Indian PKU patients.
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Codón sin Sentido/genética , Mutación INDEL/genética , Fenilalanina Hidroxilasa/genética , Fenilcetonurias/genética , Alelos , Pueblo Asiatico/genética , Análisis Mutacional de ADN , Femenino , Humanos , India , Masculino , Linaje , Fenilalanina Hidroxilasa/metabolismo , Fenilcetonurias/etiología , Fenilcetonurias/patología , Sitios de Empalme de ARN/genéticaRESUMEN
Gaucher disease (GD) is the most common glycolipid storage disorder resulting from glucocerebrosidase deficiency due to mutations in the GBA gene. Study was performed in 33 unrelated patients with low ß-glucosidase activity in leukocytes and/or fibroblasts. The exons and exon-intron boundaries of the GBA gene were bidirectionally sequenced using an automated sequencer. Mutations were confirmed in parents and were looked up in public databases, and in silico analysis was carried for novel mutations. We identified two novel missense mutations G289A (c.866G>C) and I466S (c.1397T>G) in exons 7 and 10, respectively, in two (6.06%) patients that destabilize the protein structure. L444P (c.1448T>C) was the most common mutation identified in 20/33 (60.60%) non-neuronopathic and 1/33 (3.03%) sub-acute neuronopathic form based on clinical presentation at the time of investigation. Other nine rare mutations were: R463C (c.1504C>T), R395C (c.1300C>T), R359Q (c.1193G>A), G355D (c.1181G>A), V352M (c.1171G>A) and S356F (c.1184C>T) found in each patient (18.18%). Compound heterozygous mutation L444P (c.1448T>C)/R496C (c.1603C>T) in exon 10/11 and L444P (c.1448T>C)/R329C (c.1102C>T) were observed in exon 10/8 in one each patient (6.06%). Two patients (6.06%) from Sri Lanka showed E326K (c.1093G>A) mutation in exon 8. We conclude that L444P is the most common mutant allele with exons 8 and 10 as the hot spot region of GBA gene observed in Indian GD patients.
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Enfermedad de Gaucher/genética , Glucosilceramidasa/genética , Adolescente , Adulto , Alelos , Niño , Preescolar , Estudios de Cohortes , Exones , Femenino , Humanos , India , Lactante , Masculino , Mutación , Adulto JovenRESUMEN
OBJECTIVES: To estimate the economic burden of patients diagnosed with Gaucher disease at a public hospital from a societal perspective. METHODS: Data from 30 Gaucher patients visiting the Genetic Clinic of the Department of Pediatrics at the study site in Mumbai was analyzed between January 2019 and January 2021. A cost of illness analysis was undertaken to estimate direct, indirect and intangible costs. Costs in treated and treatment naive groups were compared. RESULTS: The total cost (direct and indirect) for 30 patients was â¹25,45,74,743/- (3440199.2 USD). Majority of this cost (99.8%) was due to direct costs of which medications [Enzyme replacement therapy (ERT) and Substrate reduction therapy (SRT)] constituted 98.8%. The notional cost was â¹1,43,94,695. Total costs of 14 treated patients were â¹25,29,67,279 and 16 treatment naive patients were â¹16,15,064 with a ratio of 157:1. Direct costs and cost of school absenteeism were significantly higher in the treated subgroup. Overall, direct, total costs and costs of school absenteeism were significantly associated with age and disease duration. CONCLUSIONS: The economic burden of Gaucher disease is a staggering amount. This is an underestimate, as the expenses are highly subsidized in a public health facility. The highest contributor to cost component was direct costs, especially medication costs. Against the backdrop of the National Policy for Rare Diseases, resource allocation towards Gaucher disease should consider short term measures for judicious funding or reimbursement of disease-specific therapy and long-term cost-effective measures for promoting preventive strategies as the most practically feasible solution to reduce this economic burden.
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Enfermedad de Gaucher , Humanos , Niño , Estrés Financiero , Atención Terciaria de Salud , Costo de Enfermedad , Costos de los Medicamentos , Costos de la Atención en SaludRESUMEN
A girl in the early adolescent age group presented with multisystem manifestations in the form of periodic fever, recurrent abdominal pain, hypertension, seizure, skin lesions over the chest and gangrene over the left ring and middle fingertips. Her condition had remained undiagnosed for 11 years. On evaluation, she had features of polyarteritis nodosa (PAN) (multiple aneurysms, symmetric sensorimotor peripheral neuropathy, superficial ulcers, digital necrosis, myalgia, hypertension and proteinuria). As childhood PAN is a phenocopy of adenosine deaminase 2 with a different management strategy, whole-exome sequencing was performed, which revealed a pathogenic variant in ADA2 gene. The child was treated with TNF alpha inhibitors and showed improvement in the Paediatric Vasculitis Activity Score. The paper highlights the gratifying consequences of correct diagnosis with disease-specific therapy that ended the diagnostic odyssey, providing relief to the patient from debilitating symptoms and to the family from the financial burden of continued out-of-pocket health expenditure.
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Adenosina Desaminasa , Poliarteritis Nudosa , Humanos , Poliarteritis Nudosa/diagnóstico , Poliarteritis Nudosa/tratamiento farmacológico , Adenosina Desaminasa/deficiencia , Adenosina Desaminasa/genética , Femenino , Diagnóstico Diferencial , Adolescente , Secuenciación del Exoma , Enfermedades Autoinflamatorias Hereditarias/diagnóstico , Enfermedades Autoinflamatorias Hereditarias/genética , Enfermedades Autoinflamatorias Hereditarias/tratamiento farmacológico , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Niño , Péptidos y Proteínas de Señalización IntercelularRESUMEN
BACKGROUND: Rare disorders comprise of ~ 7500 different conditions affecting multiple systems. Diagnosis of rare diseases is complex due to dearth of specialized medical professionals, testing labs and limited therapeutic options. There is scarcity of data on the prevalence of rare diseases in different populations. India being home to a large population comprising of 4600 population groups, of which several thousand are endogamous, is likely to have a high burden of rare diseases. The present study provides a retrospective overview of a cohort of patients with rare genetic diseases identified at a tertiary genetic test centre in India. RESULTS: Overall, 3294 patients with 305 rare diseases were identified in the present study cohort. These were categorized into 14 disease groups based on the major organ/ organ system affected. Highest number of rare diseases (D = 149/305, 48.9%) were identified in the neuromuscular and neurodevelopmental (NMND) group followed by inborn errors of metabolism (IEM) (D = 47/305; 15.4%). Majority patients in the present cohort (N = 1992, 61%) were diagnosed under IEM group, of which Gaucher disease constituted maximum cases (N = 224, 11.2%). Under the NMND group, Duchenne muscular dystrophy (N = 291/885, 32.9%), trinucleotide repeat expansion disorders (N = 242/885; 27.3%) and spinal muscular atrophy (N = 141/885, 15.9%) were the most common. Majority cases of ß-thalassemia (N = 120/149, 80.5%) and cystic fibrosis (N = 74/75, 98.7%) under the haematological and pulmonary groups were observed, respectively. Founder variants were identified for Tay-Sachs disease and mucopolysaccharidosis IVA diseases. Recurrent variants for Gaucher disease (GBA:c.1448T > C), ß-thalassemia (HBB:c.92.+5G > C), non-syndromic hearing loss (GJB2:c.71G > A), albinism (TYR:c.832 C > T), congenital adrenal hyperplasia (CYP21A2:c.29-13 C > G) and progressive pseudo rheumatoid dysplasia (CCN6:c.298T > A) were observed in the present study. CONCLUSION: The present retrospective study of rare disease patients diagnosed at a tertiary genetic test centre provides first insight into the distribution of rare genetic diseases across the country. This information will likely aid in drafting future health policies, including newborn screening programs, development of target specific panel for affordable diagnosis of rare diseases and eventually build a platform for devising novel treatment strategies for rare diseases.
Asunto(s)
Enfermedades Raras , Humanos , India/epidemiología , Enfermedades Raras/genética , Estudios Retrospectivos , Masculino , Femenino , Centros de Atención Terciaria , Niño , Adulto , Adolescente , Preescolar , Adulto Joven , LactanteRESUMEN
The present study examined referral pattern and diagnostic practices for mucopolysaccharidosis (MPS) in India in 40 patients with a confirmed diagnosis. Time lag between age of onset of symptoms and consultation with primary physician ranged from 0 to 84 months, between consultation with primary physician and visit to genetic clinic of 0 to 128 months, from visit to genetic clinic and diagnosis of 1 to 111 months, and that between onset of symptoms and diagnosis 1 to 154 months. Major causes for delayed diagnosis were symptoms overlooked by physician (54%), late consultation by care giver (48.6%), late onset of symptoms (43.2%), and resource crunch (32.4%). Diagnosis at referral other than MPS was noted in 45%. Thus, diagnostic delay for MPS is common due to health seeking practices of parents, as well as physicians' clinical practices. Overcoming these barriers would necessitate strengthening awareness and educational activities for physicians and lay public.
RESUMEN
Diagnosis of rare disorders requires heightened clinical acumen. When such disorders present with atypical or novel features, it adds to the diagnostic challenge. A 9-month-old female infant who had received a diagnosis of neonatal hepatitis due to cytomegalovirus infection at 2 months of age presented to our institute with developmental delay, fever, vomiting, feeding difficulty, breathlessness and features of elevated intracranial pressure due to hydrocephalus. Key examination findings with cholestatic jaundice as an early manifestation led to suspicion of type 4 Farber disease. Observation of hydrocephalus, hypertension, bilateral pinguecula and Erlenmeyer flask deformity of the femur were unusual findings for Farber disease. The child had few features (pinguecula, Erlenmeyer flask deformity and hydrocephalus) overlapping with Gaucher disease. Alternatively, prosaposin deficiency (Farber disease type 7) was another differential diagnosis. Diagnosis of Farber disease was confirmed by detection of foamy macrophages on skin biopsy and two homozygous missense variants in ASAH1 gene.
Asunto(s)
Lipogranulomatosis de Farber , Enfermedad de Gaucher , Niño , Femenino , Fémur , Enfermedad de Gaucher/complicaciones , Enfermedad de Gaucher/diagnóstico , Enfermedad de Gaucher/genética , Humanos , Lactante , Recién Nacido , Mutación Missense , PielRESUMEN
Glutaric acidemia type 1 (GA-1, OMIM 231670) is an autosomal recessive inborn error of metabolism caused by the deficiency of glutaryl-coenzyme A (CoA) dehydrogenase with most children presenting in infancy with encephalopathy, dystonia, and macrocephaly. In this article, we presented the clinical characteristics, molecular profile, and outcomes in 29 unrelated families with affected children (30 cases total). The mean age at onset of illness was 10 months (±14.58), whereas the mean age at referral for molecular diagnosis was 29.44 months (±28.11). Patients were residents of nine different states of India. Clinical presentation varied from acute encephalitis followed by neuroregression and chronic/insidious developmental delay. Neurological sequelae varied from asymptomatic (no sequelae, 2 patients) to moderate (5 patients) and severe (23 patients) sequelae. All patients underwent blood tandem mass spectrometry (TMS on dried blood spots) and/or urine gas chromatography mass spectrometry (GCMS). Neuroimaging demonstrated batwing appearance in 95% cases. Sanger's sequencing of GCDH , covering all exons and exon-intron boundaries, was performed for all patients. Variants identified include 15 novel coding variants: p.Met100Thr, p.Gly107Ser, p.Leu179Val, p.Pro217Ser, p. Phe236Leufs*107, p.Ser255Pro, p.Met266Leufs*2, p.Gln330Ter, p.Thr344Ile, p.Leu345Pro, p.Lys377Arg, p.Leu424Pro, p.Asn373Lys, p.Lys377Arg, p.Asn392Metfs*9, and nine known genetic variants such as p.Arg128Gln, p.Leu179Arg, p.Trp225Ter, p.Met339Val, p.Gly354Ser, p.Arg402Gln, p.Arg402Trp, p.His403Tyr, and p.Ala433Val (Ensembl transcript ID: ENST00000222214). Using in silico analysis, genetic variants were shown to be affecting the residues responsible for homotetramer formation of the glutaryl-CoA dehydrogenase protein. Treatment included oral carnitine, riboflavin, protein-restricted diet, lysine-deficient special formulae, and management of acute crises with intravenous glucose and hydration. However, the mortality (9/30, 27.58%) and morbidity was high in our cohort with only two patients affording the diet. Our study is the largest multicentric, genetic variant-proven series of glutaric aciduria type 1 from India till date.