title: Analysis of serotonin receptor 2A gene (HTR2A): association study with autism spectrum disorder in the Indian population and investigation of the gene expression in peripheral blood leukocytes.
abstract: Several studies suggest involvement of serotoninergic system in the pathophysiology of Autism Spectrum Disorder (ASD). The 5-HT receptor binding studies using (3)H-lysergic acid diethylamide ((3)H-LSD) and linkage analysis provided evidences to consider HTR2A as a potential candidate gene for ASD. The three SNPs, -1438A/G (rs6311), 102T/C (rs6313) and 1354C/T (rs6314) of HTR2A have been well studied in the etiology of various neuropsychiatric disorders. But studies on association of this gene with ASD are limited to two reports from American and Korean populations. Additionally there are reports, which demonstrated paternal imprinting of HTR2A with expression from only one allele. So far no reports are available on HTR2A and its association with any neuropsychiatric disorders from Indian population. Therefore, the present study investigates association of the above mentioned three markers of HTR2A with ASD in Indian population using population and family-based approaches. The study also deals with allelic expression pattern of HTR2A in Peripheral Blood Leukocytes (PBLs) to understand the parental imprinting status. The genotyping analyses were carried out for probands, parents and controls. The subsequent association analyses did not show association of these markers with ASD. So, HTR2A is unlikely to be a genetic marker for ASD in Indian population. The expression analyses showed absence of monoallelic expression, suggesting lack of parental imprinting of HTR2A gene. However, we noticed methylation of the CpG sites at -1438A/G and 102T/C loci of HTR2A gene. Further bioinformatics analysis revealed absence of CpG islands in the promoter of the gene supporting biallelic expression pattern of HTR2A in PBLs.
authors: Manovikas Biomedical Research and Diagnostic Centre, Manovikas Kendra, Rehabilitation and Research Institute for the Handicapped, 482 Madudah, Plot I-24, Sector-J, EM Bypass, Kolkata 700107, India.
authors: Subhrangshu
authors: S
authors: Guhathakurta
authors: Asem Surindro
authors: AS
authors: Singh
authors: Swagata
authors: S
authors: Sinha
authors: Anindita
authors: A
authors: Chatterjee
authors: Shabina
authors: S
authors: Ahmed
authors: Saurabh
authors: S
authors: Ghosh
authors: Rajamma
authors: R
authors: Usha
mesh_terms: D000328:Adult; D001321:Autistic Disorder / Q000208:ethnology / Q000235:genetics* / Q000378:metabolism; D001923:Brain Chemistry / Q000235:genetics; D002478:Cells, Cultured; D002648:Child; D018899:CpG Islands / Q000235:genetics; D019175:DNA Methylation / Q000235:genetics; D004252:DNA Mutational Analysis; D044127:Epigenesis, Genetic / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics*; D005787:Gene Frequency / Q000235:genetics; D005819:Genetic Markers / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005820:Genetic Testing; D018392:Genomic Imprinting / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007194:India / Q000208:ethnology; D040582:Inheritance Patterns / Q000235:genetics; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D044402:Receptor, Serotonin, 5-HT2A / Q000235:genetics*; D012701:Serotonin / Q000378:metabolism
chemical_list: D005819:Genetic Markers; D044402:Receptor, Serotonin, 5-HT2A; D012701:Serotonin