1. Das DK, Mehta B, Menon SR, Raha S, Udani V. {{Novel Mutations in Cyclin-Dependent Kinase-Like 5 (CDKL5) Gene in Indian Cases of Rett Syndrome}}. {Neuromolecular Med};2012 (Dec 15)
Rett syndrome is a severe neurodevelopmental disorder, almost exclusively affecting females and characterized by a wide spectrum of clinical manifestations. Both the classic and atypical forms of Rett syndrome are primarily due to mutations in the methyl-CpG-binding protein 2 (MECP2) gene. Mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene have been identified in patients with atypical Rett syndrome, X-linked infantile spasms sharing common features of generally early-onset seizures and mental retardation. CDKL5 is known as serine/threonine protein kinase 9 (STK9) and is mapped to the Xp22 region. It has a conserved serine/threonine kinase domain within its amino terminus and a large C-terminal region. Disease-causing mutations are distributed in both the amino terminal domain and in the large C-terminal domain. We have screened the CDKL5 gene in 44 patients with atypical Rett syndrome who had tested negative for MECP2 gene mutations and have identified 6 sequence variants, out of which three were novel and three known mutations. Two of these novel mutations p.V966I and p.A1011V were missense and p.H589H a silent mutation. Other known mutations identified were p.V999M, p.Q791P and p.T734A. Sequence homology for all the mutations revealed that the two mutations (p.Q791P and p.T734A) were conserved across species. This indicated the importance of these residues in structure and function of the protein. The damaging effects of these mutations were analysed in silico using PolyPhen-2 online software. The PolyPhen-2 scores of p.Q791P and p.T734A were 0.998 and 0.48, revealing that these mutations could be deleterious and might have potential functional effect. All other mutations had a low score suggesting that they might not alter the activity of CDKL5. We have also analysed the position of the mutations in the CDKL5 protein and found that all the mutations were present in the C-terminal domain of the protein. The C-terminal domain is required for cellular localization through protein-protein interaction; any mutations in this domain might alter this function of the protein. This is the first report from India showing the mutation in CDKL5 gene in Indian cases of Rett syndrome. Our study emphasizes the role of CDKL5 mutation screening in cases of atypical Rett syndrome with congenital seizure variant.
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2. Lofthouse N, Hendren R, Hurt E, Arnold LE, Butter E. {{A review of complementary and alternative treatments for autism spectrum disorders}}. {Autism Res Treat};2012;2012:870391.
Given the severe and chronic problems associated with Autism Spectrum Disorders (ASD) and the limitations of available treatments, there exists a large public health need for additional interventions. As more parents are inquiring about complementary and alternative treatments (CATs), both parents and practitioners require up-to-date information about them and whether and how to integrate them into treatment. After presenting data on CAT usage patterns for ASD, we review 13 ingestible (i.e., orally administered) and 6 noningestible (i.e., externally administered) CATs for ASD. For each CAT we briefly describe its definition; rationale for use; current research support, limitations, and future directions; safety issues; and whether we currently recommend, not recommend, or find it acceptable for the treatment of ASD. We conclude this paper with recommendations for future research and ten clinical recommendations for practitioners.
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3. Lu AT, Dai X, Martinez-Agosto JA, Cantor RM. {{Support for calcium channel gene defects in autism spectrum disorders}}. {Mol Autism};2012 (Dec 15);3(1):18.
ABSTRACT: BACKGROUND: Alternation of synaptic homeostasis is a biological process whose disruption might predispose children to autism spectrum disorders (ASD). Calcium channel genes (CCG) contribute to modulating neuronal function and evidence implicating CCG in ASD has been accumulating. We conducted a targeted association analysis of CCG using existing genome-wide association study (GWAS) data and imputation methods in a combined sample of parent/affected child trios from two ASD family collections to explore this hypothesis. METHODS: A total of 2,176 single-nucleotide polymorphisms (SNP) (703 genotyped and 1,473 imputed) covering the genes that encode the alpha1 subunit proteins of 10 calcium channels were tested for association with ASD in a combined sample of 2,781 parent/affected child trios from 543 multiplex Caucasian ASD families from the Autism Genetics Resource Exchange (AGRE) and 1,651 multiplex and simplex Caucasian ASD families from the Autism Genome Project (AGP). SNP imputation using IMPUTE2 and a combined reference panel from the HapMap3 and the 1,000 Genomes Project increased coverage density of the CCG. Family-based association was tested using the FBAT software which controls for population stratification and accounts for the non-independence of siblings within multiplex families. The level of significance for association was set at 2.3E-05, providing a Bonferroni correction for this targeted 10-gene panel. RESULTS: Four SNPs in three CCGs were associated with ASD. One, rs10848653, is located in CACNA1C, a gene in which rare de novo mutations are responsible for Timothy syndrome, a Mendelian disorder that features ASD. Two others, rs198538 and rs198545, located in CACN1G, and a fourth, rs5750860, located in CACNA1I, are in CCGs that encode T-type calcium channels, genes with previous ASD associations. CONCLUSIONS: These associations support a role for common CCG SNPs in ASD.
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4. Sasaki K. {{[Effect of tracheostomy with imipramine on apneusis attacks in a girl with Rett syndrome]}}. {No To Hattatsu};2012 (Nov);44(6):492-495.
A girl with Rett syndrome was suffered from severe apneusis attacks, resulting in cardiopulmonary arrest, which required resuscitation. Her apneusis attacks did not respond at all to diazepam, magnesium citrare or tricyclic antidepressants but ceased by tracheostomy with oral imipramine. The breathing abnormality appeared to involve difficulty in terminating inspiration. This supports the idea that a lack of serotonin may cause her apneusis attacks.
