Abstract:

Mathematics is an essential subject related to many fields such as science, engineering, economics, and medicine, which are of great and increasing importance for the development of modern society. In recent years, many studies using quantitative genetics, which adopted the twin-study design, were conducted to identify the heritability of performance related to mathematical ability and disability. Although the underlying mechanism is poorly understood, the qualitative behavioral genetics study demonstrated that mathematical abilities are moderately heritable. However, extant evidence was mainly obtained from quantitative genetic research, solely reported by a few molecular genetic studies, which specifically investigated mathematical ability or disability. To the best of our knowledge, till date, only a single molecular genetic study has investigated the effect of the gene (G) × environment (E) interactions on mathematical ability in children. The present study was designed to extend the previous research by examining the effect of the interaction between brain-derived neurotrophic factor (BDNF) gene rs6265 polymorphism and parent-involved education (PIE) on the basic mathematical ability in primary school children. Further, we assessed these two competing models, the classic diathesis-stress model vs. the newly developed differential susceptibility model.
Primary school (PS) children (n = 602, male = 297, female = 305) from 23 classes ranging from grade-3 to grade-6 were included in the study. Their basic mathematical ability was assessed using the Chinese rating scale of pupil’s mathematical abilities and PIE was examined by employing a behavior questionnaire of pupil’s PIE (version answered by parents). The genomic DNA of PS children was extracted from their saliva samples. Genotyping of these DNA samples to identify rs6265 polymorphism in BDNF was performed using real-time PCR with MassARRAY RT software version 3.0.0.4 and analyzed using MassARRAY typer software version 4.0. A series of linear regression statistical analyses were conducted using statistical package for social sciences software version 19.0. Further, re-parameterized regression models were constructed to examine the effect of the interaction between BDNF rs6265 polymorphism and PIE on basic mathematical ability in PS children using the two potential competing G × E hypotheses.
In this study, we obtained three major results, which are as follows: (1) BDNF rs6265 polymorphism was significantly associated with logical thinking (LT) and spatial vision (SV) abilities in PS children. Especially, PS children carrying the AA genotype exhibited a better performance of LT and SV abilities compared to PS children carrying the G allele. (2) The interaction between rs6265 polymorphism and PIE substantially predicted LT and SV abilities in PS children. The PIE behavior positively predicted LT and SV abilities among PS children carrying the G allele but not the AA genotype. (3) The indexes in re-parameterized regression models supported the strong diathesis-stress model.
In conclusion, by elaborating the moderating effect of PIE, the present study enriches the literature on the association between BDNF rs6265 polymorphism and basic mathematical ability in PS children. This study expands our knowledge regarding the G × E underpinnings of basic mathematical ability and the novel as well as newly developed methods, which are proving to be highly efficient and legitimate.

Key words: BDNF gene rs6265 polymorphism, mathematical abilities, parent-involved education, gene ×, environment interaction;, primary school children