Thursday, May 12, 2011
Elizabeth Ballroom E-F and Lirenta Foyer Level 2 (Manchester Grand Hyatt)
3:00 PM
J. Montalvo1, M. Echegaray2, R. E. Oliveras-Rentas3, L. Deliz-Bauza4, S. F. Acevedo5, M. S. Collazo6, S. Carlo7, L. Alvarado8, V. Velazquez8, X. Negroni8, Y. Hernandez8 and M. Vazquez-Correa9, (1)Child Neurology Program, University of Puerto Rico Medical Sciences, San Juan, PR, (2)Biology Department, University of Puerto Rico-Cayey, Cayey, PR, (3)Department of Psychiatry and Human Behavior, Ponce School of Medicine , Ponce, PR, (4)Ponce School of Medicine and Health Sciences, Clinical Psychology Program, Ponce, PR, (5)Physiology Department, Ponce School of Medicine, Ponce, PR, (6)Physiology Department, Ponce School of Medicine, Ponce, PR, (7)Biochemistry Department, Ponce School of Medicine , Ponce, PR, (8)Pediatrics, St. Luke's Memorial Hospital, Ponce, PR, (9)Child Neurology Program, University of Puerto Rico Medical Sciences Campus, San Juan, PR
Background: Autism is a neurodevelopmental disorder characterized by stereotypic and repetitive behaviors and interests, together with social and communicative deficiencies. Various genomic scans have identified the 19p13.2 and 19q13.4 loci as having possible linkage with autism spectrum disorder. Within this region is the apolipoprotein E (APOE) gene, which codes for a protein, whose different isoforms (E2, E3, E4) affect neuronal growth and development. Previous studies on the possible association between APOE gene variants and autism have produced contradictory results.
Objectives: To test the hypothesis of association between the APOE gene variants (E2, E3, E4) and autism disorder in a cohort of Puerto Rican children.
Methods: A case-control study was performed with 50 patients, aged 3-12 y.o, diagnosed with Autism and 55 unrelated age-matched control subjects. Genomic material was collected from buccal swabs. The amplification of the APOE gene was carried out by PCR and the polymorphic variants were identified by restriction fragment length polymorphism and agarose gel electrophoresis.
Results: We found no significant difference in allele frequency between autistic (4% E2, 91% E3, 5% E4) and control (4% E2, 85% E3, 11% E4) children (Χ2 = 3.69, df =2, P = 0.15). However, we did find a significant difference for genotype frequency with autistic children (8% E2/E3, 86% E3/E3, 6% E3/E4) showing a lower frequency of the E3/E4 genotype than controls (7% E2/E3, 71% E3/E3, 22% E3/E4); (Χ2= 17.5, df = 2, P = 0.0002).
Conclusions: The results of the present study support the hypothesis of association between genotype, based on the APOE variants, and autism in our cohort of Puerto Rican children. In particular, significant underrepresentation of the E3/E4 genotype was observed in group of autistic subjects, supporting the possible involvement of apolipoprotein in the development of autism.
