Objective To explore the associations of the sub-components of central executive function ( inhibition, shifting and updating) with monoamine oxidase A ( MAOA ) and dopamine-β-hydroxylase ( DBH ).Methods The cognitive performance of the 719 healthy individuals,who were selected randomly from an university in Xi' an,was assessed by the world wide used paradigms of central executive function. Then, a populationbased study was performed to analysis the associations of central executive function with the 30-bp variable number tandem repeat and -C1021T in the promoters of MAOA and DBH ,respectively. Results The results indicated that the 30-bp variable number tandem repeat of MAOA was associated with the performance of inhibition and updating ( x2 = 4.82,4.50; P= 0. 03,0.03 ) in males. The reaction time of inhibition test was shorter in 3r genotype group ( (671.32 ±9.77 )ms) than that in 4r genotype group ( (706.61 ± 14.58 ) ms) ,and the indivudals with 3r genotype (47.85 ±0. 69) had more updating numbers than the indivudals with 4r (45.13 ± 1. 05). However, there was no significant association of the -C1021T and DBH with the components of excutive function (P＞0.05). Conclusion The present study suggests that the 30-bp variable number tandem repeat of MAOA contributs to the inhibition in males while -C1021T of DBH has no striking effects on the components of executive function in males and females.

Objective To explore the relationship between interleukin 1 receptor accessory protein-like 2 (IL1RAPL2) gene and cognitive abilities of children in Qin-Ba mountainous region. Methods Four tagged SNPs (rs5962434,rs5916817, rs3764765 and rs5962298 ) in IL1RAPL2 were selected, and then genotyped by PCR-SSCP method in a 320 children sample aged from six to fourteen years old. Results The results showed the rs5962434, rs5916817 ,rs3764765 and rs5962298 had no deviations from Hardy-Weinberg equilibrium (P＞0.05),and there were no significant statistical differences in the average psychometric scores of general cognitive ability(P=0.81,0.53,0.79,0.90) ,verbal comprehension (P=0.58,0.47,0.69,0.87 ) ,memory and concentration (P=0.69,0.35,0.76,0.90) among the compared genotype groups at each of the markers. Furthermore,the results also indicated that the four SNPs were not associated with perceptual organization in males and females respectively (P = 0.70,0.85,0.76,0.90,0.65,0.22,0.98,0.90 ). Conclusion The present work suggests that the human general cognitive ability, the three cognitive factors of C-WISC scale are not influenced manifestly by the genetic variations in IL1RAPL2.