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1.
Curr Microbiol ; 81(9): 301, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39115704

RESUMEN

The limited literature on the clinical course of COVID-19 among patients with underlying liver disease (LD) is available from India. The present study aimed to evaluate the clinical and mutational profile of SARS-CoV-2 among LD cases. This was a retrospective study including admitted LD cases in whom SARS-CoV-2 RT-PCR testing was performed. Complete demographic and clinical details were retrieved from Hospital Information System. Detailed mutational analysis was performed by comparing LD COVID-19 positive study group, i.e. LD-CoV(+) with COVID-19 positive outpatients without any underlying LD as control, i.e. NLD-CoV(+). Out of 232 enrolled LD cases, 137 (59.1%) were LD-CoV(+). LD cases with existing co-morbidities were affected more (P = 0.002) and had 2.29 times (OR 2.29, CI 95%, 1.25-4.29) higher odds of succumbing to COVID-19 (P = 0.006). On multivariate regression analysis, ascites (P = 0.05), severe COVID-19 pneumonia (P = 0.046), and an increased levels of bilirubin (P = 0.005) and alkaline phosphatase (P = 0.003) were found to be associated with adverse outcome in LD-CoV(+).On mutational analysis, we found certain differences between LD- and NLD-CoV(+) infected with Delta [LD- and NLD-CoV (+ /D)] and Omicron [LD- and NLD-CoV(+/O)]. More mutations were shared between LD- and NLD-CoV(+/O) compared to LD- and NLD-CoV(+/D). There were differences in prevalence of indel mutations specific to LD-CoV ( +) for both Delta and Omicron. Moreover, we also reported an interesting genic bias between LD- and NLD-CoV( +) in harbouring deleterious/tolerated mutations. To conclude, LD cases with comorbidities were affected more and had higher odds of mortality due to COVID-19. The definite difference between LD- and NLD-CoV(+) groups with respect to frequency of harboured mutations and an inherent genic bias between them is of noteworthy importance.


Asunto(s)
COVID-19 , Hepatopatías , SARS-CoV-2 , Humanos , COVID-19/virología , COVID-19/genética , Estudios Retrospectivos , Masculino , Femenino , SARS-CoV-2/genética , Persona de Mediana Edad , Hepatopatías/virología , Hepatopatías/genética , Adulto , India/epidemiología , Anciano , Mutación , Comorbilidad
2.
Hum Genome Var ; 11(1): 25, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38871700

RESUMEN

Tandem nucleotide repeat (TNR) expansions, particularly the CNG nucleotide configuration, are associated with a variety of neurodegenerative disorders. In this study, we aimed to identify novel unstable CNG repeat loci associated with the neurogenetic disorder spinocerebellar ataxia (SCA). Using a computational approach, 15,069 CNG repeat loci in the coding and noncoding regions of the human genome were identified. Based on the feature selection criteria (repeat length >10 and functional location of repeats), we selected 52 repeats for further analysis and evaluated the repeat length variability in 100 control subjects. A subset of 19 CNG loci observed to be highly variable in control subjects was selected for subsequent analysis in 100 individuals with SCA. The genes with these highly variable repeats also exhibited higher gene expression levels in the brain according to the tissue expression dataset (GTEx). No pathogenic expansion events were identified in patient samples, which is a limitation given the size of the patient group examined; however, these loci contain potential risk alleles for expandability. Recent studies have implicated GLS, RAI1, GIPC1, MED15, EP400, MEF2A, and CNKSR2 in neurological diseases, with GLS, GIPC1, MED15, RAI1, and MEF2A sharing the same repeat loci reported in this study. This finding validates the approach of evaluating repeat loci in different populations and their possible implications for human pathologies.

3.
Int Orthod ; 22(2): 100869, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38513309

RESUMEN

OBJECTIVE: To assess the allele rs 1143634 in IL-1ß and rs1800587 in IL-1α in patients for orthodontically induced external apical root resorption (EARR). MATERIAL AND METHODS: Intra-oral periapical radiograph (IOPA) of maxillary incisors of 142 Patients were evaluated for resorption at two time points; before the start of fixed mechanotherapy (T1) and after one year of treatment (T2). The individuals with root resorption<2mm were categorized as a control group (group 1; n=90), and resorption>2mm were categorized as case group (group 2; n=52). Buccal swabs of all patients were taken and DNA could be isolated in 95 out of 142 samples (group 1 {n=58}, group 2 {n=37}), which were then screened for the selected two polymorphic targets to determine the nucleotide status of these targets. Tetra-primer ARMS PCR reactions were carried out using all 4 primers for each polymorphism. RESULTS: rs11800587 was not associated with risk of EARR in any inheritance model. Chi-square test for association of alleles with EARR revealed that rs1143634 was associated with the risk of EARR in an allelic model in such a way that A allele of this SNP increased the risk of EARR 4 folds [OR=4.375; P=0.016]. However, the adjusted level of significance using the Holm-Bonferroni method for rs1143634 was P<0.010 for A and G comparison rendering the results non-significant. CONCLUSION: SNP rs1143634 and SNP rs11800587 were not associated with risk of EARR in any inheritance model.


Asunto(s)
Interleucina-1alfa , Interleucina-1beta , Polimorfismo de Nucleótido Simple , Resorción Radicular , Adolescente , Niño , Femenino , Humanos , Masculino , Adulto Joven , Alelos , Estudios de Casos y Controles , Incisivo , Interleucina-1alfa/genética , Interleucina-1beta/genética , Resorción Radicular/genética , Resorción Radicular/etiología
4.
Neurogenetics ; 25(1): 13-25, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37917284

RESUMEN

An intronic bi-allelic pentanucleotide repeat expansion mutation, (AAGGG)400-2000, at AAAAG repeat locus in RFC1 gene, is known as underlying genetic cause in cases with cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) and late-onset sporadic ataxia. Biallelic positive cases carry a common recessive risk haplotype, "AAGA," spanning RFC1 gene. In this study, our aim is to find prevalence of bi-allelic (AAGGG)exp in Indian ataxia and other neurological disorders and investigate the complexity of RFC1 repeat locus and its potential association with neurodegenerative diseases in Indian population-based cohorts. We carried out repeat number and repeat type estimation using flanking PCR and repeat primed PCR (AAAAG/AAAGG/AAGGG) in four Indian disease cohorts and healthy controls. Haplotype assessment of suspected cases was done by genotyping and confirmed by Sanger sequencing. Blood samples and consent of all the cases and detailed clinical details of positive cases were collected in collaboration with A.I.I.M.S. Furthermore, comprehension of RFC1 repeat locus and risk haplotype analysis in Indian background was performed on the NGS data of Indian healthy controls by ExpansionHunter, ExpansionHunter Denovo, and PHASE analysis, respectively. Genetic screening of RFC1-TNR locus in 1998 uncharacterized cases (SCA12: 87; uncharacterized ataxia: 1818, CMT: 93) and 564 heterogenous controls showed that the frequency of subjects with bi-allelic (AAGGG)exp are 1.15%, < 0.05%, 2.15%, and 0% respectively. Two RFC1 positive sporadic late-onset ataxia cases, one bi-allelic (AAGGG)exp and another, (AAAGG)~700/(AAGGG)exp, had recessive risk haplotype and CANVAS symptoms. Long normal alleles, 15-27, are significantly rare in ataxia cohort. In IndiGen control population (IndiGen; N = 1029), long normal repeat range, 15-27, is significantly associated with A3G3 and some rare repeat motifs, AGAGG, AACGG, AAGAG, and AAGGC. Risk-associated "AAGA" haplotype of the original pathogenic expansion of A2G3 was found associated with the A3G3 representing alleles in background population. Apart from bi-allelic (AAGGG)exp, we report cases with a new pathogenic expansion of (AAAGG)exp/(AAGGG)exp in RFC1 and recessive risk haplotype. We found different repeat motifs at RFC1 TNR locus, like AAAAG, AAAGG, AAAGGG, AAAAGG, AAGAG, AACGG, AAGGC, AGAGG, and AAGGG, in Indian background population except ACAGG and (AAAGG)n/(AAGGG)n. Our findings will help in further understanding the role of long normal repeat size and different repeat motifs, specifically AAAGG, AAAGGG, and other rare repeat motifs, at the RFC1 locus.


Asunto(s)
Ataxia Cerebelosa , Enfermedades del Sistema Nervioso Periférico , Enfermedades Vestibulares , Humanos , Ataxia Cerebelosa/genética , Ataxia Cerebelosa/diagnóstico , Ataxia
5.
Microbiol Spectr ; 10(2): e0272921, 2022 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-35311567

RESUMEN

Since its advent, the pandemic has caused havoc in multiple waves due partly to amplified transmissibility and immune escape to vaccines. Delhi, India also witnessed brutal multiple peaks causing exponential rise in cases. Here we had retrospectively investigated clade variation, emergence of new lineages and varied clinical characteristics during those three peaks in order to understand the trajectory of the ongoing pandemic. In this study, a total of 123,378 samples were collected for a time span of 14 months (1 June 2020 to 3 August 2021) encompassing three different peaks in Delhi. A subset of 747 samples was processed for sequencing. Complete clinical and demographic details of all the enrolled cases were also collected. We detected 26 lineages across three peaks nonuniformly from 612 quality passed samples. The first peak was driven by diverse early variants, while the second one by B.1.36 and B.1.617.2, unlike third peak caused entirely by B.1.617.2. A total of 18,316 mutations with median of 34 were reported. Majority of mutations were present in less than 1% of samples. Differences in clinical characteristics across three peaks was also reported. To be ahead of the frequently changing course of the ongoing pandemic, it is of utmost importance that novel lineages be tracked continuously. Prioritized sequencing of sudden local outburst and community hot spots must be done to swiftly detect a novel mutation/lineage of potential clinical importance. IMPORTANCE Genome surveillance of the Delhi data provides a more detailed picture of diverse circulating lineages. The added value that the current study provides by clinical details of the patients is of importance. We looked at the shifting patterns of lineages, clinical characteristics and mutation types and mutation load during each successive infection surge in Delhi. The importance of widespread genomic surveillance cannot be stressed enough to timely detect new variants so that appropriate policies can be immediately implemented upon to help control the infection spread. The entire idea of genomic surveillance is to arm us with the clues as to how the novel mutations and/or variants can prove to be more transmissible and/or fatal. In India, the densely populated cities have an added concern of the huge burden that even the milder variants of the virus combined with co-morbidity can have on the community/primary health care centers.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Genómica , Humanos , Mutación , Filogenia , Estudios Retrospectivos , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética
7.
Adv Genet (Hoboken) ; 3(2): 2100078, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36618024

RESUMEN

Cerebellar ataxias (CAs) represent a group of autosomal dominant and recessive neurodegenerative disorders affecting cerebellum with or without spinal cord. Overall, CAs have preponderance for tandem nucleotide repeat expansions as an etiological factor (10 TREs explain nearly 30-40% of ataxia cohort globally). The experience of 10 years of common genetic ataxia subtypes for ≈5600 patients' referrals (Pan-India) received at a single center is shared herein. Frequencies (in %, n) of SCA types and FRDA in the sample cohort are observed as follows: SCA12 (8.6%, 490); SCA2 (8.5%, 482); SCA1 (4.8%, 272); SCA3 (2%, 113); SCA7 (0.5%, 28); SCA6 (0.1%, 05); SCA17 (0.1%, 05), and FRDA (2.2%, 127). A significant amount of variability in TRE lengths at each locus is observed, we noted presence of biallelic expansion, co-occurrence of SCA-subtypes, and the presence of premutable normal alleles. The frequency of mutated GAA-FRDA allele in healthy controls is 1/158 (0.63%), thus an expected FRDA prevalence of 1:100 000 persons. The data of this study are relevant not only for clinical decision making but also for guidance in direction of genetic investigations, transancestral comparison of genotypes, and lastly provide insight for policy decision for the consideration of SCAs under rare disease category.

8.
Brain Commun ; 3(1): fcaa214, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33501421

RESUMEN

Autosomal Dominant Cortical Tremor, Myoclonus and Epilepsy is a non-progressive disorder characterized by distal tremors. Autosomal Dominant Cortical Tremor, Myoclonus and Epilepsy has been reported globally with different genetic predispositions of autosomal dominant inheritance with a high degree of penetrance. In south India, Autosomal Dominant Cortical Tremor, Myoclonus and Epilepsy has been reported in a large cohort of 48 families, in which the genetic defect was not identified. This report pertains to the whole-genome analysis of four individuals followed by repeat-primed PCR for 102 patients from a familial cohort of 325 individuals. All the patients underwent extensive clinical evaluation including neuropsychological examinations. The whole-genome sequencing was done for two affected and two unaffected individuals, belonging to two different families. The whole-genome sequencing analysis revealed the repeat expansion of TTTTA and TTTCA in intron 4 of the SAMD12 gene located on chromosome 8 in the patients affected with Autosomal Dominant Cortical Tremor, Myoclonus and Epilepsy, whereas the unaffected family members were negative for the similar expansion. Further, the repeat-primed PCR analysis of 102 patients showed the expansion of the TTTCA repeats in the intron 4 of SAMD12 gene. All patients registered for this study belong to a single community called "Nadar" whose nativity is confined to the southern districts of India, with reported unique genetic characteristics. This is the largest and most comprehensive single report on clinically and genetically characterized Autosomal Dominant Cortical Tremor, Myoclonus and Epilepsy patients belonging to a unique ethnic group worldwide.

9.
J Huntingtons Dis ; 9(3): 283-289, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32675418

RESUMEN

BACKGROUND: The diagnostic workup for choreiform movement disorders including Huntington's disease (HD) and those mimicking HD like phenotype is complex. OBJECTIVE: The aim of the present study was to genetically define HD and HD-like presentations in an Indian cohort. We also describe HTT-CAG expansion manifesting as neuroferritinopathy-like disorder in four families from Punjab in India. MATERIALS AND METHODS: 159 patients clinically diagnosed as HD and HD-like presentations from various tertiary neurology clinics were referred to our centre (CSIR-IGIB) for genetic investigations. As a first tier test, CAG-TNR for HTT was performed and subsequently HD-negative samples were screened for JPH3 (HDL2), TBP (SCA17), ATN1 (DRPLA), PPP2R2B (SCA12) and GGGGCC expansion in C9orf72 gene. Four families presenting as neuroferritinopathy-like disorder were also investigated for HTT-CAG expansion. RESULTS: 94 of 159 (59%) patients were found to have expanded HTT-CAG repeats. Pathogenic repeat expansion in JPH3, TBP, ATN1 and C9orf72 were not found in HD negative cases. Two patients were positive for SCA12-CAG expansion in pathogenic length, whereas 5 cases harboured TBP-CAG repeats falling in reduced penetrance range of 41- 48 repeats for SCA17. Four unrelated families, presented with atypical chorea and brain MRI findings suggestive of basal ganglia abnormalities mimicking neuroferritinopathy were found to harbour HTT-CAG expansion. CONCLUSION: We present SCA12 as a new reported phenocopy of HD which should be considered for diagnostic workout along with SCA17 for HD-like syndromes. This study also illustrates the necessity, to consider evolving HD like phenotype, as a clinical diagnosis for cases with initial manifestations depicting neuroferritinopathy.


Asunto(s)
Trastornos Heredodegenerativos del Sistema Nervioso/diagnóstico , Enfermedad de Huntington/diagnóstico , Trastornos del Metabolismo del Hierro/diagnóstico , Distrofias Neuroaxonales/diagnóstico , Expansión de Repetición de Trinucleótido/genética , Adulto , Femenino , Pruebas Genéticas , Trastornos Heredodegenerativos del Sistema Nervioso/genética , Humanos , Proteína Huntingtina , Enfermedad de Huntington/genética , India , Trastornos del Metabolismo del Hierro/genética , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso , Distrofias Neuroaxonales/genética , Proteína Fosfatasa 2 , Proteína de Unión a TATA-Box
10.
Neurobiol Aging ; 88: 156.e1-156.e9, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32035847

RESUMEN

Hexanucleotide repeat expansion in C9orf72 is defined as a major causative factor for familial amyotrophic lateral sclerosis (ALS). The mutation frequency varies dramatically among populations of different ethnicity; however, in most cases, C9orf72 mutant has been described on a common founder haplotype. We assessed its frequency in a study cohort involving 593 clinically and electrophysiologically defined ALS cases. We also investigated the presence of reported Finnish haplotype among the mutation carriers. The identified common haplotype region was further screened in 192 (carrying 2-6 G4C2 repeats) and 96 (≥7 repeats) control chromosomes. The G4C2 expansion was observed in 3.2% (19/593) of total cases where 9/19 (47.4%) positive cases belonged to the eastern region of India. Haplotype analysis revealed 11 G4C2-Ex carriers shared the common haplotype (haplo-A) background spanning a region of ∼90 kbp (rs895021-rs11789520) including rs3849942 (a well-known global at-risk loci with T allele for G4C2 expansion). The other 3 G4C2-Ex cases had a different haplotype (haplo-B) with core difference from haplo-A at G4C2-Ex flanking 31 kbp region between rs3849942 and rs11789520 SNPs (allele 'C' of rs3849942 which is a nonrisk allele). Out of other five G4C2-cases, four carried the risk allele T of rs3849942 while one harbored the non-risk allele. This study establishes the prevalence of C9orf72 expansion in Indian ALS cases providing further evidence for geographical predilection. The global core risk haplotype predominated C9orf72 expansion-positive ALS cases, yet the existence of a different haplotype suggests a second lineage (haplo B), which may have been derived from the Finnish core haplotype or may imply a unique haplotype among Asians. The association of risk haplotype with normal intermediate C9orf72 alleles reinforced its role in conferring instability to the C9orf72-G4C2 region. We thus present an effective support to interpret future burden of ALS cases in India.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Proteína C9orf72/genética , Expansión de las Repeticiones de ADN/genética , Estudios de Asociación Genética , Mutación , Alelos , Estudios de Cohortes , Haplotipos , Heterocigoto , India , Riesgo
11.
eNeurologicalSci ; 17: 100211, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31737797

RESUMEN

Spinocerebellar ataxia type 10 (SCA10) is a rare autosomal dominant cerebellar ataxia caused by nucleotide ATTCT expansion in ATXN10 gene. SCA10 has been reported in patients of cerebellar ataxia from Amerindian/Latin America and in East Asian ancestry. A common founder has been ascribed to the origin of ATTCT repeat expansion mutation in both the population. Here we present our investigation of the SCA10 pentanucleotide repeat expansion in 461 SCA patients of the Indian population. The analysis of multi-ethnic at-risk haplotype C-(ATTCT)n-GGC was performed using genotype data of various ethnic population included in the 1000 Genomes Project (KGP) to infer the prevalence of at-risk haplotype in the Indian populations. Unsurprisingly, none of the patient's DNA samples with (ATTCT)n expansion was observed in pathological range, however, the observed normal range of (ATTCT)n was 8-22 repeats, suggesting very rare or absence of the occurrence of SCA10 in Indian SCA patients. The at-risk haplotype, CGGC was found to be the most prevalent haplotype across different populations and no segregation of CGGC haplotype with large normal or small normal ATTCT repeats length was observed. However, on extended haplotype analysis, some lineage of CGGC with a flanking divergence at 5' end was observed specifically in the American or East Asian population but not in other population in KGP dataset. Together, these evidence points towards the absence of SCA10 in Indian population and haplotype-based analysis also suggests its occurrence to be rare in South Asian, European and African population. Further investigations are required to establish the present finding. SIGNIFICANCE: The implications of the findings of this study are 1.) For the diagnostic work-up of SCAs in the Indian population and to decide upon inclusion of SCA10 in panel based genetic investigations even for Indians living abroad. 2.) The haplotype based inference of its presumptive prevalence through the estimation of at-risk haplotype using population genetics approach (South-Asians as the background) allowed us to estimate the possible absence of SCA10 in Indian population. SCA10 is a rare autosomal dominant cerebellar ataxia mostly reported among SCA patients from Latin America and recently described in East Asia population. The genetic study of SCA10 performed in the unrelated Indian spinocerebellar ataxia patients with heterogeneous ethnicity confirmed its absence from the Indian population and that conforms to population genetic based inference of its rarity or absence. 3.) This approach may be adopted for the screening of other subtypes of SCAs, i.e. other rare SCAs e.g. SCA31, SCA36, and SCA37.

12.
Clin Genet ; 96(6): 566-574, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31429931

RESUMEN

Over 100 genetically distinct causal known loci for hereditary ataxia phenotype poses a challenge for diagnostic work-up for ataxia patients in a clinically relevant time and precision. In the present study using next-generation sequencing, we have investigated pathogenic variants in early-onset cerebellar ataxia cases using whole exome sequencing in singleton/family-designed and targeted gene-panel sequencing. A total of 98 index patients were clinically and genetically (whole exome sequencing (WES) in 16 patients and targeted gene panel of 41 ataxia causing genes in 82 patients) evaluated. Four families underwent WES in family based design. Overall, we have identified 24 variants comprising 20 pathogenic and four likely-pathogenic both rare/novel, variations in 21 early onset cerebellar ataxia patients. Among the identified variations, SACS (n = 7) and SETX (n = 6) were frequent, while ATM (n = 2), TTPA (n = 2) and other rare loci were observed. We have prioritized novel pathogenic variants in RARS2 and FA2H loci through family based design in two out of four families.


Asunto(s)
Secuenciación del Exoma , Genes Recesivos , Variación Genética , Degeneraciones Espinocerebelosas/genética , Adulto , Secuencia de Bases , Familia , Sitios Genéticos , Predisposición Genética a la Enfermedad , Humanos , Mutación/genética
13.
Sex Dev ; 13(5-6): 228-239, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32894851

RESUMEN

The aim of this study was to assess the prevalence of pathogenic variants in the SRD5A2 gene in children with 46,XY disorders of sex development (DSD) with normal to high serum testosterone levels and absence of Müllerian structures on imaging and to evaluate the genotype-phenotype correlation. Seventy-five patients with 46,XY DSD and probable clinical diagnosis of 5α-reductase 2 deficiency or androgen insensitivity syndrome were enrolled. Genetic analysis was done for pathogenic variants in SRD5A2, and the genotype-phenotype correlation was studied. As a result, 10 pathogenic or likely pathogenic biallelic variants in SRD5A2, either homozygous or compound heterozygous, were identified in 25 of 75 (33.3%) patients. The hCG stimulated testosterone: dihydrotestosterone (T:DHT) ratio was elevated in all patients with pathogenic variants in SRD5A2 and in nearly 90% of those without pathogenic variants in SRD5A2 in whom this was assessed. The missense pathogenic variant p.R246Q was a hotspot. One novel pathogenic variant p.Y178*, and a variant p.F194I, not previously reported in patients with 5α-reductase 2 deficiency, were identified. The missense variant p.F194I was predicted as deleterious and damaging by in silico analysis and as likely to reduce the enzyme activity by protein modeling. In conclusion, pathogenic variants in SRD5A2 can be detected in a wide spectrum of Indian patients with 46,XY DSD. Molecular genetic analysis should be considered as a first-line test as the T:DHT ratio lacks specificity and a hotspot variant is present in a vast majority.

14.
Ann Hum Genet ; 81(5): 197-204, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28597910

RESUMEN

Spinocerebellar ataxia type 7 (SCA7) is a rare neurogenetic disorder caused by highly unstable CAG repeat expansion mutation in coding region of SCA7. We aimed to understand the effect of diverse ATXN7 cis-element in correlation with CAG expansion mutation of SCA7. We initially performed an analysis to identify the haplotype background of CAG expanded alleles using eight bi-allelic single nucleotide polymorphisms (SNPs) flanking an ATXN7-CAG expansion in 32 individuals from nine unrelated Indian SCA7 families and 88 healthy controls. Subsequent validation of the findings was performed in 89 ATXN7-CAG mutation carriers and in 119 unrelated healthy controls of Mexican ancestry. The haplotype analyses showed a shared haplotype background and C allele of SNP rs6798742 (approximately 6 kb from the 3'-end of CAG repeats) is in complete association with expanded, premutation, intermediate, and the majority of large normal (≥12) CAG allele. The C allele (ancestral/chimp allele) association was validated in SCA7 subjects and healthy controls from Mexico, suggesting its substantial association with CAG expanded and expansion-prone chromosomes. Analysis of rs6798742 and other neighboring functional SNPs within 6 kb in experimental datasets (Encyclopedia of DNA Elements; ENCODE) shows functional marks that could affect transcription as well as histone methylation. An allelic association of the CAG region to an intronic SNP in two different ethnic and geographical populations suggests a -cis factor-dependent mechanism in ATXN7 CAG-region expansion.


Asunto(s)
Ataxina-7/genética , Expansión de las Repeticiones de ADN , Polimorfismo de Nucleótido Simple , Ataxias Espinocerebelosas/genética , Estudios de Asociación Genética , Haplotipos , Humanos , India , México
15.
J Neurol Sci ; 373: 55-57, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28131227

RESUMEN

Pathogenic expansion of a hexanucleotide repeat in C9orf72 is associated with ~30% of familial ALS and ~7% of sporadic ALS patients amongst different populations. This repeat expansion was screened in 75 ALS patients and 115 healthy individuals from North India. On analysis by repeat-primed PCR, pathogenic expansion was not observed either in ALS patients or healthy controls. These observations are similar to the findings in most of the Asian populations.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Expansión de las Repeticiones de ADN , Proteínas/genética , Adulto , Edad de Inicio , Anciano , Esclerosis Amiotrófica Lateral/fisiopatología , Pueblo Asiatico/genética , Proteína C9orf72 , Femenino , Técnicas de Genotipaje , Humanos , India , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
16.
Neurol Res ; 38(1): 69-74, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26883819

RESUMEN

BACKGROUND: Polymorphisms of G174C and C572G in the interleukin-6 (IL-6) promoter gene can affect both transcription and secretion of IL-6 and may be involved in inflammation related to and pathogenesis of ischemic stroke (IS). Whether these IL-6 gene polymorphisms are risk factors for IS or not, remains controversial. OBJECTIVE: The aim of this study was to determine the association between IL-6 G174C and C572G gene polymorphisms and susceptibility to ischemic stroke in North Indian Population. METHODS: Two hundred and fifty IS patients and 250 age- and sex-matched controls were studied. Genotyping was performed using SNaPshot method. Stroke was classified using Trial of Org 10172 in acute stroke treatment classification. Conditional logistic regression analysis was used to calculate the strength of association between IL-6 (G174C and C572G) polymorphisms and risk of IS. RESULTS: Hypertension, diabetes, dyslipidemia, alcohol, smoking, family history of stroke, sedentary life style and low socioeconomic status were found to be associated with the risk of IS. Conditional logistic regression analysis showed a significant association of IL-6 G174C with the risk of IS under dominant model (OR, 1.61; 95%CI, 1.0-2.4; P value 0.02) and allelic model (OR, 1.5; 95%CI, 1.0-2.1; P value 0.02). For IL-6 C572G, multivariate adjusted analysis showed a significant association with the risk of IS under dominant model for overall IS (OR, 1.81; 95%CI, 1.04-3.15; P value 0.03) and small vessel disease subtype of IS (OR, 2.8; 95%CI, 1.3-6.0; P value 0.006). CONCLUSION: Our results suggest that IL-6 (G174C) polymorphism is significantly associated with the risk of IS in North Indian population. However, IL-6 (C572G) polymorphism is found significantly associated with the risk of IS after adjusting the demographic and risk factors variables. Prospective studies with large sample size are required for independent validation. Our findings could be helpful in identifying individuals at increased risk for developing IS.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Interleucina-6/metabolismo , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genética , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/genética , Adulto , Isquemia Encefálica/complicaciones , Estudios de Casos y Controles , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Neuroimagen , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Accidente Cerebrovascular/diagnóstico por imagen
17.
Meta Gene ; 7: 34-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26862479

RESUMEN

BACKGROUND: Genetic factors may play a role in the susceptibility of Ischemic stroke (IS). Previous studies have shown that Tumour necrosis factor-α (TNF-α) gene polymorphisms were associated with the risk of IS in multiple ethnicities. The present case-control study tested the hypothesis that genetic polymorphisms of the TNF-α gene may affect the risk of IS in North Indian population. We investigated the association of four single nucleotide polymorphisms (- 308G/A, + 488G/A, - 857C/T and -1031 T/C) within TNF-α gene promoter and their haplotypes with the risk of IS. METHODS: IS was classified using the Trial of Org 10,172 in Acute Stroke Treatment (TOAST) classification. Genotyping was performed for 250 IS patients and 250 age- and sex-matched IS free controls by using SNaPshot technique. Multivariate logistic regression was used to control the confounding effects of demographic and risk factor variables. Haplotype analyses were done by using PHASE software and Linkage disequilibrium (LD) analyses were done by using Haploview version 4.2 software. RESULTS: An independent association between TNF-α + 488G/A (OR = 2.59; 95%CI 1.46 to 4.60; p = 0.001) and -857C/T (OR = 1.77; 95%CI 1.01 to 3.11; p < 0.04) and risk of IS was observed under dominant model. However, no significant association between -308G/A and -1031 T/C gene polymorphisms and risk of IS was observed. Haplotype analysis showed that A308-G488-C857-T1031 haplotypes were significantly associated with the increased risk of IS [OR = 1.66; 95%CI 1.02 to 2.71; p = 0.003]. Strong linkage disequilibrium (LD) was observed for + 488G/A and -857C/T (D' = 0.41, r(2) = 0.004). CONCLUSIONS: Two SNPs (+ 488G/A and -857C/T) of TNF-α gene and their haplotypes are significantly associated with the risk of IS in the population enrolled from North India. Our findings indicate that polymorphisms and haplotypes of TNF-α gene may be used as a genetic marker for identifying individuals at increased risk for developing IS.

18.
J Stroke Cerebrovasc Dis ; 25(2): 461-8, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26654671

RESUMEN

BACKGROUND: Anti-inflammatory interleukin-10 (IL-10) cytokine and its genetic variations may play an important role in the pathogenesis of various human diseases including stroke. OBJECTIVE: The aim of this present case-control study was to determine the association between IL-10 -1082G/A (rs1800896) gene polymorphism and risk of stroke in the North Indian population. METHODS: Genotyping was carried out by using SNaPshot method (Applied Biosystems, Foster City, California, United States) for 250 ischemic stroke (IS) patients, 250 age- and sex-matched IS free controls, 100 intracerebral hemorrhage (ICH) patients, and 100 age- and sex-matched ICH free controls. IS was classified using the Trial of Org 10172 in Acute Stroke Treatment classification. Conditional logistic regression analysis with adjustment for multiple demographic and risk factor variables was used to calculate the strength of association between IL-10 (-1082G/A) polymorphism and risk of stroke. RESULTS: Conditional logistic regression analysis showed an independent association between IL-10 -1082G/A and risk of IS under a dominant model (odds ratio [OR] = 2.39, 95% confidence interval [CI] = 1.34-4.27, P = .003) and an allelic model (OR = 2.49, 95% CI 1.71-3.63, P < .001). An independent association between IL-10 -1082G/A, under the dominant model (OR = 6.8, 95% CI 2.2-20.7, P < .001) and the allelic model (OR = 3.4, 95% CI 1.8-6.3, P < .001), and the risk of ICH was also observed. CONCLUSION: Our results suggest that IL-10 -1082G/A gene polymorphism is an independent risk factor for the risk of IS and ICH in the North Indian population. Our findings indicate that IL-10 -1082G/A polymorphism may be used as a genetic marker for identifying individuals at increased risk of developing stroke.


Asunto(s)
Predisposición Genética a la Enfermedad , Genotipo , Interleucina-10/genética , Polimorfismo de Nucleótido Simple , Accidente Cerebrovascular/genética , Adulto , Anciano , Alelos , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Humanos , India , Masculino , Persona de Mediana Edad
19.
Parkinsonism Relat Disord ; 20(10): 1089-93, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25085749

RESUMEN

BACKGROUND: Fragile X-associated Tremor/Ataxia syndrome (FXTAS) is a clinically heterogeneous disorder characterized predominantly by tremor, followed by late onset gait ataxia, autonomic dysfunction and/or cognitive impairment. We aimed to screen FMR1-CGG repeats in our cohort of progressive late-onset cerebellar ataxia/tremor cohort to characterize the occurrence of FXTAS in India. METHODS: We have screened FMR1-CGG repeats in 109 patients and 173 healthy control subjects. Our cohort comprised: a)group of patients with predominant cerebellar ataxia and/or tremor. b.)suspected cases of MSA and c.)patients who presented SCA12-like neurological manifestations (late onset predominant tremor and/or ataxia). All the cases were ruled out for known triplet-repeat-expansion (TRE) SCA mutations. RESULTS: We have found three FMR1-premutation carriers among the cases. Two of them (with CGG-96 and CGG-102) were under evaluation for their SCA12-like manifestations and another (CGG-78) had progressive gait ataxia. Overall the frequency of FXTAS in our cohort was found to be 3.3% among cases of late onset cerebellar-ataxia/tremor; however, incidences were higher among cases with SCA12-like syndrome (9%, 2/23). CONCLUSION: Finding FXTAS in patients with SCA12-like manifestation suggests that TRE in the 5'UTR of the gene is the common cue connecting two disorders with common phenotype of tremor/ataxia. This knowledge might shed light upon their sharing of molecular neuropathology.


Asunto(s)
Ataxia/diagnóstico , Ataxia/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/diagnóstico , Síndrome del Cromosoma X Frágil/genética , Ataxias Espinocerebelosas/fisiopatología , Temblor/diagnóstico , Temblor/genética , Repeticiones de Trinucleótidos/genética , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , India/epidemiología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/genética , Fenotipo , Proteína Fosfatasa 2/genética , Ataxias Espinocerebelosas/genética
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