RESUMO
To identify if COMT polymorphisms interact with executive functions as predictors of math skills, we assessed 38 adolescents (mean age = 16.4 ± 0.80 years, IQ > 80) from a larger study of high-school students screened for their mathematical abilities. Adolescents were genotyped for the COMT Val158Met polymorphism (grouped as Met/Met or Val-carriers) and completed the WRAT math achievement test, working-memory, inhibitory-control, and shifting tasks. Met/Met-carriers achieved higher WRAT scores than the Val-carriers (W = 229, p = .009). Genotype group was a moderate-to-strong predictor of WRAT scores (ß = 0.56 to 0.74). No genotype/executive-function interaction was detected. Our findings suggest that the rs4680 Met/Met genotype is positively associated with math achievement.
Assuntos
Cognição , Função Executiva , Adolescente , Humanos , Genótipo , Memória de Curto Prazo , Catecol O-Metiltransferase/genéticaRESUMO
The objective of this study was to characterize an attention deficit hyperactivity disorder (ADHD) endophenotype in non-affected parents of adolescents with a history of ADHD, based on the relationship between performance on a sustained attention test (continuous performance task, or CPT) and polymorphisms of the DRD4 gene. In a sample of 25 non-affected parents of adolescents with ADHD history obtained from a longitudinal study of a nonclinical population, and 25 non-affected parents of adolescents with no ADHD history, four groups were evaluated with respect to the presence or absence of the long allele polymorphism of the DRD4 gene (i.e., over seven repeats). Comparisons of CPT performance among the four study groups included the number of commission errors, the number of omission errors, mean reaction time on correct responses (MRT), and reaction time (RT) variability (mean standard deviation of RT in each block [SDRT, as variability], and the sigma and tau components of the ex-Gaussian approach). The group of non-affected parents of adolescents with ADHD history and at least one long allele of the DRD4 gene showed greater RT variability (measured by SDRT), which is best explained by the greater frequency of abnormally slow responses (measured by tau). An association between the presence of the long allele of the DRD4 gene polymorphism and ADHD-like failure in CPT performance was evident in the non-affected parents of adolescents with ADHD in childhood. These findings suggest that certain traits of CPT performance could be considered an ADHD endophenotype.
Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Receptores de Dopamina D4/genética , Adulto , Alelos , Atenção/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Cognição/fisiologia , Endofenótipos , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Pais , Polimorfismo de Nucleotídeo Único/genética , Tempo de Reação/genética , Receptores de Dopamina D4/sangueRESUMO
We report the fifth female patient with Myhre syndrome (MS) and review the literature. She is a 13-year-old Mexican girl whose phenotype fulfills all the clinical and radiological criteria reported in MS such as typical facies, short stature, limited joint mobility, and short hands and feet. The physical habitus of MS is described and a square body shape is clearly distinguished in all cases. As the typical muscular build is present mainly in male patients, the MS muscular appearance may be hormonally influenced.
