The Characteristics Of Clinical And Neuropsychodevelopment In Children With Autistic Disorder And Its Detection Of FMR-1 Gene And Polymorphism Study Of BDNF Gene

Objective: The study aimed to analyse clinical and neuropsychodevelopment characteristics of children autistic disorder, its detection of FMR-1 gene and explore the candidate gene through study the relation between children autistic disorder and polymorphisms of BDNF gene.Method: Seventy-five outpatients were recruited from Mental Health Center of West China Hospital, Sichuan University.Using Childhood Autism Rating Scale(CARS), Autism Behavior Checklist( ABC) , Clancy Autism Behavior Scale(CABs), Children adaptable behavior Scale, Parent Temperament Questionnaire and Children development Questionnaire to evaluate or investigate. The diagnosis of children autistic disorder is based on ICD-10 and CCMD-3 criteria. According to the assumption of dysfunction in neurodevelopment of autism, we analysed the association between autistic disorder and 196G/A (Val66Met) SNP and dinucleotide repeat polymorphism of brain-derived neurotrophic factor(BDNF) gene in 75 autistic nuclear trios using Transmission/disequilibrium test (TDT).Result: 1.Usually children suffered from autism before two years old but visited doctor after three years old; 2. There were multiple perinatal high risk factors in children with autism. There was close relationship between mother's depression and anxiety during pregnancy and asphyxia after birth and umbilical cord winding the neck of fetus and children autism; 3.The adaptable level was lower in 77.3% autistic children. In severe autistic children, the adaptable level was much lower than that in minor and moderate ones; 4.The abnormal frequency of FMR-1 gene was very lower (1.3%) in children with autism; 5.There was no evidence for linkage disequilibrium between two polymorphisms in the BDNF gene and children autistic disorder. 6.There was a linkage disequilibrium between dinucleotide repeat polymorphism of BDNF gene and severe autism ( **=7.31, P=0.025) .7. Allele Al (174bp)and allele A3(170bp) of dinucleotide repeat polymorphism of BDNF gene may influence adaptable level of autistic children through Allele Al restrained the experience of autistic symptoms and Allele A3 promoted it; 8. Autistic symptoms may be restrained when there is a mutation from allele G to allele A of 196G/A single-nucleotide polymorphism(SNP) of BDNF gene; 9. There may be some basis of inherited mechanism in partial factors of Parent Temperament Questionnaire (PTQ) because of a significant statistical correlation between factor 2 and factor 7 of PTQ and 196G/A SNP of BDNF gene.Conclusion: The results suggest that prevention, diagnosis and treatment should be carried out as early as possible because there are multiple perinatal high risk factors for the autism and autistic symptoms deterioratethe adaptive level of patient. There may be a different inherited mechanism in minor and moderate autistic disorder and in severe ones. Theory of neurodevelopmental handicap may be pathogeny of autistic disorder since dinucleotide repeat polymorphism of BDNF gene may influence the development of children autistic disorder.