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Background: Autonomic dysfunction is common in children with Rett syndrome. They usually manifest with agitation, persistent screaming, constipation, gastroesophageal reflux, aerophagia, hyperventilation, and breath-holding episodes. Cardiovascular autonomic dysfunction may result in fatal a arrhythmia. Many of these events are mistaken for seizures and treated with antiepileptics.Methods: The present study was conducted in a tertiary care teaching hospital in north India for more than a six month period. MeCP2 mutation positive, 24 cases with Rett syndrome and 24 age-matched healthy girls were evaluated for cardiovascular autonomic dysfunction (heart rate variability, head-up tilt test, and cold pressor test).Results: The mean age was 9.06 years (±3.4) and 9.75 years (±3.13) for patients and control subjects, respectively. The heart rate variability contributed independently by parasympathetic and sympathetic nervous system was significantly reduced in cases compared with control subjects (P = 0.033 and P = 0.001, respectively). There was significant sympathovagal imbalance with sympathetic overactivity in cases compared with control subjects (P = 0.001). The mean longest QTc interval was significantly prolonged in cases compared with control subjects (P = 0.001). Cold pressor test and head-up tilt test could be done in 16 Rett syndrome patients (because of poor cooperation) and in all 24 control subjects. The change in blood pressure during cold pressor test and head-up tilt test was not significantly different in cases and control subjects.Conclusions: Children with Rett syndrome exhibited significant cardiovascular autonomic dysfunction in the form of sympathetic overactivity, parasympathetic underactivity, and sympathovagal imbalance. These findings have potentially important therapeutic- and outcome-related implications. [ABSTRACT FROM AUTHOR]

Abstract: Background: X-linked Adrenoleukodystrophy (X-ALD), with an incidence of 1:14,000 is the most frequent monogenic demyelinating disorder worldwide. The principal biochemical abnormality in X-ALD is the increased levels of saturated, unbranched very long chain fatty acids (VLCFA). It is caused by mutations in ABCD1 gene. No molecular data on X-ALD is available in India and mutational spectrum in Indian patients is not known. Methods: We standardized conformation sensitive gel electrophoresis (CSGE) method to detect mutations in ABCD1 gene in twenty Indian patients with X-ALD. The results were confirmed by sequencing. Genotype–phenotype correlation was also attempted. Prenatal diagnosis (PND) in one family was done using chorionic villi (CV) sample at 12weeks of gestation. Results: Out of twenty, causative mutations could be identified in twelve patients (60%). Six reported and four novel mutations were identified. Three polymorphisms were also observed. No hot spot was found. No significant genotype–phenotype correlation could be established. Conclusions: The study identified the mutation spectrum of Indian X-ALD patients, which enabled us to offer accurate genetic counseling, carrier detection and prenatal diagnosis where needed. [Copyright &y& Elsevier]

Background Acute necrotizing encephalopathy (ANE) is a rare disorder characterized by encephalopathy following a febrile illness, mostly viral. Most cases are sporadic; however, recurrent and familial cases have been linked to RANBP2 mutation. Description of the case This is a description of a three and half years old girl with recurrent ANE with RANBP2 mutation (c.1754 C > T (p.T585M)). She had two episodes of encephalopathy, each following a short non-specific febrile illness. Neuroradiologically, she had typical findings involving bilateral thalami during the first episode and involving bilateral temporal and occipital lobes, bilateral cerebellar hemispheres and brainstem during the second episode. She was managed with intravenous gamma globulin and dexamethasone during both the episodes. She recovered significantly with residual deficits in her cognitive and language domains. Conclusions In relevant clinic-radiological scenarios both isolated and recurrent ANE should be considered because of treatment and long-term outcome related implications. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Rett syndrome (RS), an X-linked neurodevelopmental disorder and the common cause of mental retardation in females, is caused by methyl CpG binding protein 2 (MECP2) gene mutations with a frequency of more than 95% in classical Rett patients. Majority of RS cases are sporadic but few familial cases caused by either skewed X-chromosome inactivation in healthy female carriers or mosaicism in male carriers are also reported. Most of the times, the mutation carried in a family is the same as found in affected child. Methods and results: Here we report a unique family carrying non-identical MECP2 mutations in exon 2 wherein the proband with classical RS was carrying a de-novo early truncating frameshift mutation while her asymptomatic mother was carrying a missense mutation, both predicted as pathogenic mutations. Conclusions: These findings further validate the importance of MECP2 mutation screening in parents of all mutation positive patients and careful evaluation of the pathogenicity of the mutation found in asymptomatic carriers before providing genetic counseling to the family. The results also propose the role of other factors including other gene mutations, environmental and epigenetics factors in modifying the expression of MECP2 mutations. [Copyright &y& Elsevier]

Mutations in the MLC1 gene cause megalencephalic leukoencephalopathy with subcortical cysts. We sought to identify mutations in the MLC1 gene, to evaluate the genotype-phenotype correlation, and to develop a strategy for diagnosing Indian patients with megalencephalic leukoencephalopathy. Forty patients were enrolled. We developed a rapid restriction fragment length polymorphism method to screen a common mutation, c.135_136insC. Rare and novel mutations were screened by conformation-sensitive gel electrophoresis, followed by sequencing. Three previously reported and two novel mutations were identified in 37 patients. The presence of the c.135_136insC mutation in 29 patients of the Agarwal community suggests a founder effect. The mutation c.959C>A was evident in four patients, and appears to be the second commonest mutation. Genotype could not predict phenotype. We recommend screening for the commonest mutation (c.135_136insC), followed by the next commonest mutation (c.959C>A), and then other rare mutations, using conformation-sensitive gel electrophoresis analysis or direct sequencing. [ABSTRACT FROM AUTHOR]

Abstract: Metachromatic leukodystrophy (MLD) is an autosomal recessive disorder caused by mutations in arylsulfatase A (ARSA) gene. No work on molecular genetics of MLD has been reported from India and the mutational spectrum in Indian patients is not known. The present study was undertaken to identify mutations in arylsulfatase A gene in Indian MLD patients, to evaluate genotype–phenotype correlation, and to see the effect of the novel mutants on the protein. Twenty MLD patients (16 families) were screened by ARMS PCR for the most common mutation (c.459+1G>A). Pseudodeficiency alleles were tested by RFLP method whereas rare and novel mutations were scanned by Conformation Sensitive Gel Electrophoresis (CSGE), followed by sequencing. The genotype–phenotype correlation was also attempted. Protein homology modeling analysis was carried out for two novel missense mutations identified, to assess the effect of these mutations on the protein conformation. Nine pathogenic alleles were found in 13 patients (65%). Four previously reported mutations and five novel variants were identified. Five patients (35%) were found to have pseudodeficiency alleles, c.1049A>G (p.Asn350Ser) and c.1524+95A>G. Genotype–phenotype correlation was found to be difficult to establish. Protein modeling studies showed that the mutations cause loss of interactions leading to conformational change in ASA protein. The study identified the mutational spectrum of Indian MLD patients, which will be helpful in genetic counseling, carrier detection and establishing prenatal diagnosis. Homology modeling helped to study conformational change in protein and has implications in generating novel therapeutic molecules. [ABSTRACT FROM AUTHOR]