Correlação entre o polimorfismo thr92ala da enzima iodotironina desiodase tipo II e funções cognitivas na Síndrome de Down
Arquivos
Tipo
Dissertação
Data de publicação
2017-03-27
Periódico
Citações (Scopus)
Autores
Batistuzzo, Alice
Orientador
Ribeiro, Miriam Oliveira
Título da Revista
ISSN da Revista
Título de Volume
Membros da banca
Carreiro, Luiz Renato Rodrigues
Pinto, Carla
Pinto, Carla
Programa
Distúrbios do Desenvolvimento
Resumo
About 12 to 36% of the population presents homozygosis for a polymorphism in enzyme
deiodinase type 2 (Thr92Ala-D2). Positive correlations were found between point
mutations in D2 and intellectual disability, bipolarity and psychosis. It has recently been
shown that this mutation leads to modifications in the cellular transcriptome in human
brains that appear to relate to changes in pathways involved in the modulation of cognitive
development and in Parkinson's disease, Alzheimer's and schizophrenia. Down Syndrome
(DS) is the most common autosomal aneuploidy, affecting on average 1/660 newborns
and represents about 18% of the total number of mentally handicapped in specialized
institutions. In addition to cognitive deficits, neuropathologies such as Alzheimer's in
individuals with DS are frequent. Based on the data described, we asked whether the
Thr92Ala-D2 mutation could contribute to changes in the cognitive functions of
individuals with DS. To answer this question, the presence of Thr92Ala-D2 in 29 children
with DS, aged between 2 months and 18 years, was screened. The genotype was
determined by the PCR en real time technique. The IQ was estimated in 15 participants
by the SON-R 2 ½ - 7 and WASI instruments. The short-term memory was evaluated in
11 participants from the TIME instrument and the adaptive behavior was evaluated in 29
through the Vineland Questionnaire. The frequency found for the genotype was 20.69%
wild (T / T), 55.17% heterozygous (A / T) and 24.14% polymorphic (A / A) and similar
to that found in the population In the adaptive behavior, a significant difference was found
between the A / A polymorphic group and the wild T / T in the domains Domestic,
Interpersonal Relations, Play and Leisure and in the Social and Global Adaptive Level
domains. The IQ values ranged from 40 to 70, and in the evaluation of short-term
memory, 72.72% of the subjects had a low performance. No correlation was found
between the presence of polymorphism and IQ or memory. In future studies, it is
important to use a larger sample, with young and adult individuals, and to compare with
individuals of typical development, since strong evidence has been found in this study
that the presence of polymorphism causes impairment in the cognitive functions of
individuals with DS.
Descrição
Palavras-chave
polimorfismo , memória , inteligência , comportamento adaptativo
Assuntos Scopus
Citação
BATISTUZZO, Alice. Correlação entre o polimorfismo thr92ala da enzima iodotironina desiodase tipo II e funções cognitivas na Síndrome de Down. 2017. 55 f. Dissertação ( Distúrbios do Desenvolvimento) - Universidade Presbiteriana Mackenzie, São Paulo .