A descriptive cross-sectional study was conducted from October, 2014, to October, 2015.

Approximately half (49.7%) of the participants declared that they had studied genetics during their training as teachers, and most (69.5%) reported some knowledge about genetic influence on human behavior, mainly obtained from books, TV documentaries, the internet, and magazines.

We filled out the numerical scales by attributing substantial influences to these two factors. For personality and behavioral problems, the highest percentages of the responses fell between numbers 7 to 10 on the environment scale. For intelligence, learning difficulties, and mental disorders, the highest percentages of the responses fell between numbers 7 and 10 on the genetic scale.

The multiple choice questions regarding personality and behavioral problems obtained a mean value of above 3; intelligence and learning difficulties obtained a mean value of below 3; and mental disorders obtained a mean value of below 2, indicating perception of a greater genetic influence (Table 1). Significantly, comparison of the sample for each behavior using multiple choice questions revealed statistically significant differences (p = 0.00).

In general, the sample groups were more associated with items containing the genetic factor; the item “only environment” (IGA5) was not associated with the sample groups. The items containing the genetic factor were associated with one another, and with most of the sample groups, demonstrating great acceptance of genetic influence on all behaviors. Meanwhile, the area of knowledge (AC) groups yielded a counterintuitive result: the “human sciences” (AC1) was closer to “genes only” (IGA1), and the biological and exact science areas (AC2 and AC3) were closer to “more environment than genes” (IGA4). The income ranges, for their part, formed an association gradient: the lower the income (R1 and R2), the greater the perception of genetic influence, whereas with increasing income (R4) there was a growing perception of the environmental influence.

Women (G1) were associated with the item “more genes than environment” (IGA2), and men (G2) were associated with the item “more environment than genes” (IGA4). Regarding educational level, the groups with “higher education” and “specialization” (E1 and E2) were closer to the items “genes only” (IGA1), “more genes than environment” (IGA2), and “genes and environment in equal parts” (IGA3). Finally, the “master’s” and “doctorate or postdoctoral” groups (E3 and E4) were not associated with any item. (Figure 1).

Most of the teachers evaluated (93.8%) declared that being aware of a genetically influenced learning difficulty in one of their students would affect their method for the instruction and monitoring of this student (Figure 2). The numerical scale for the extent to which the teacher’s methods would be affected showed that 92.6% of the participants assigned numbers from 4 to 10.

This study analyzes the perceptions of teachers about how genes and environment influence intelligence, personality, learning difficulties, behavioral problems, and mental disorders, as well as their attitudes toward students with genetically influenced learning difficulties.

For the multiple choice questions, considering that item three represents the equivalent influence of genes and environment on behaviors, the mean values indicated that teachers perceived genetic and environmental influences in a balanced manner for Personality (3.17; SD = 0.79) and Learning difficulty (2.90; SD = 0.87), and attributed a greater genetic influence to Intelligence (2.57; SD = 0.88) and to Mental Disorders (1.78; SD = 0.74), along with a greater environmental influence on Behavioral Problems (3.55; SD = 0.73). The statistically significant difference between mean perception values demonstrates that teachers recognized the fact that each behavior has a dynamic of genetic and environmental influences (Asbury & Plomin, 2013).

Jointly considering the mean for all behaviors (2.79), it can be seen that the perception of genetic influence is slightly higher, although it is close to equilibrium between factors (Table 1). This general mean agrees with two previous studies: a survey of public attitudes toward human genetics, in which the ensemble of the mean values for an ample gamut of characteristics gave a result of 2.69 (Human Genetics Commission, 2001); and the study that inspired this one (Walker & Plomin, 2005), in which parents and teachers in the United Kingdom responded to the same questions as those we asked, with a general mean of 2.57 for the parents’ responses, and of 2.66 for the teachers’. These results provide information about similar perceptions of genetic and environmental influences on different groups at different time points: participants in the investigations by Snyderman and Rothman (1988), and Rindermann et al. (2016), considered a predominantly genetic influence on the difference in intelligence without ruling out the various environmental factors, and emphasized the importance of the educational environment. The perceptions of the present sample are close to recent discoveries that have detected a substantial genetic influence with the essential role of the environment on human characteristics and complex behaviors (Plomin et al., 2016; Polderman et al., 2015; Wesseldijk et al., 2017).

This view of the importance of these two factors does not hide the fact that a much greater parcel of the sample believed in gene exclusivity compared to the exclusive role of the environment. Considering the responses to the five behaviors together, 10.20% of the teachers chose the option “only genes”, while 1.20% chose the option “only environment”. These extreme positions are seen as nonsense by recent researchers (Ackerman, 2014). This is mainly because attributing individual success or failure only to the environment does not explain the reason why individuals are different, even when submitted to an identical environment (Ackerman, 2014). Failure to consider the role of genes is to deny human nature itself, as well as the entire evolutionary history inserted into our genes up to the time of conception, followed by the interactions of the genes with all possible stimuli throughout life (Pinker, 2002; Wesseldijk et al., 2017).

On the other hand, without their environment, the genes have no influences: genes respond to the environment in the phenomenon of gene-environment interaction, and the environment responds to the genes in gene-environment correlations (Briley & Tucker-Drob, 2014; Plomin et al., 2016; Tucker-Drob & Briley, 2014). The belief of trait immutability, meanwhile, can influence important decisions, such as opposition to public policies for containing social inequality (Rattan et al., 2012). Thus, a belief in biological determinism, as observed in research on teachers from different countries, is related to creationistic conceptions (Castéra & Clément, 2014), and explains intolerant attitudes regarding differences between groups (Castéra & Clément, 2014, Keller, 2005). In the educational environment, a belief in genetic determinism as fatalistic and immutable can influence the perception that student behavior cannot be changed (Ireland, 2007).

Therefore, acquiring knowledge about genetic influences and mechanisms can modify assumptions and myths about genetic determinism, such as trait immutability (Kampourakis, Reydon, Patrinos, & Strasser, 2014), and contributes to an understanding of individual behavioral differences that recognizes human nature not as an alternative to creation, but as an explanation, thus encouraging the search for the limits of a human being (Asbury & Plomin, 2013; Da Silva, 2005). As one researcher stated, “It is difficult to educate when we do not believe in the educability of each human being, and therefore the idea of a gift symbolizes giving up education and trying again despite previous failures” (Ireland, 2007, p.30).

Importantly, behaviors involving cognition, such as Intelligence and Learning Difficulties, showed a higher percentage of responses directed at genetics (51.8% for Intelligence, and 36.5% for Learning Difficulties). In contrast, domains involving social behaviors, such as Personality and Behavioral Problems, showed higher percentages of responses directed at the environment (38.6% for Personality, and 61.7% for Behavioral Problems) (Table 1).

When investigating teacher-student interaction and the students’ perceptions regarding teacher expectations, Osti and Martinelli (2014) observed that students with a satisfactory performances declared that they were more praised and chosen as helpers, whereas students with unsatisfactory performances declared that they were more criticized and considered guilty when some undisciplined event occurred in the classroom. In the light of behavioral genetics, the occurrence of a reactive or evocative gene-environment interaction is notable here, with the genetic predisposition of the students evoking specific behaviors from the persons around them (Plomin et al., 2016), in this specific case, the teacher. It has been found that any predisposition to behavioral traits is susceptible to environmental stimulation (Briley & Tucker-Drob, 2014; Plomin et al., 2016), especially considering the importance of an environment that is not shared, i.e., the specific environmental influence for each individual, which has a specialized influence (Tucker-Drob & Briley, 2014).

Both the student’s propensity to a given behavior and the teacher’s perception of it contribute to the way the teacher deals with this student. Considering the results of the cited study (Osti & Martinelli, 2014) together with the present ones, we may argue that perceiving a greater genetic influence on behaviors related to cognition may be linked to the belief in the immutability of traits, leading to a harmful reaction to differences in student performance.

However, the diversity of the teachers’ responses demonstrates that their perceptions are distributed along a continuum, not simply at two opposite points. The same occurs with the social perception of beliefs about the genetic and environmental influence on intelligence, and on its malleability or immutability, and about brain development and plasticity throughout life (Thomas & Sarnecka, 2015). More importantly, most teachers (88.57%) selected the options that consider the influence of the two factors in certain proportions (Table 1).

Correspondence analysis (Figure 1) showed that women (G1) perceive genes as having more influence on behavior (IGA2), and that men (G2) perceive the environment as having more influence (IGA4), confirming the results reported by the study of the Human Genetics Commission (2001). The same analysis showed that higher educational levels (E3 and E4) turned more towards the environmental side of the map, while lower levels (E1 and E2) were close to items representing perceptions of a predominance of genetic influence. There are similarities between these results and those of Cástera and Clément (2014), who observed that the higher the teachers’ educational levels, the lower the innate aspect detected in their responses.

Multiple choice questions further limit the teachers’ perceptions to an additive model of influences, by dividing the items into genetic and environmental portions, even in the item “genes and environment in equal parts,” which assigns 50.0% of the influence to the genes, and 50.0% to the environment. Analysis of the numerical scales, however, revealed that some of the teachers did not fill out the numeration of the scales in a complementary manner, but instead with equal or close numbers. According to this model, it can be seen that in 2.15% of cases, a value of 10 was assigned to the two scales-genetics and environment-with overlapping of item three (“genes and environment in equal parts”). This demonstrates that the teachers not only consider the influence of genes and environment, but also that they perceive the interaction between genes and environment as non-additive, or rather as interactive, to the point that they assigned the same weight to the two factors, i.e., “100.0% genetic and 100.0% environmental” (Jacquard & Kahn, 2001, p.167).

Meanwhile, in the teachers’ responses to the question of how much their teaching methods would be affected if they knew that the learning difficulty of a student is genetically influenced, 93.8% of them declared that this condition would affect in some measure their attitudes towards the student (Figure 2). The numerical scale showed that 92.6% of the teachers declared that the measure for a change in attitude would be equal to or higher than 4 on a scale from 0 to 10, with 50.0% of them assigning weights from 7 to 9. This study evaluates Brazilian teachers of all educational levels, most of whom declared that they acted on different levels at the same time. Interestingly, these results are closely similar to those reported by Walker and Plomin (2005) in a United Kingdom study, in which 82.0% of teachers of seven-year-old pupils, with the presence of twins in the classroom, declared completely or somewhat true the statement “Knowing that a student has a genetically influenced learning difficulty, would this affect your method of instructing and monitoring him.” This discovery confirms the thesis that having some type of perception about an individual affects one’s way of acting towards him (World Bank Group, 2015; Moore, 2013). As if following positive feedback, the teacher diversifies his teaching strategies when learning about the peculiarities of the student, thus expecting the student to improve his performance.

In general, teachers’ perceptions about genetic and environmental influences on the behaviors investigated is similar to the discoveries of the genetics of human development. In addition, most teachers perceived genetic patrimony and environmental as influencing in some manner the behavior of their students, and that their own teaching methods are affected because of knowing about the genetically influenced learning difficulties of some students. The percentage of perceptions exclusively directed at genetic or environmental influence was small, demonstrating erroneous beliefs in genetic and environmental determinism, although this result demonstrates that this perception is considered to be valid by only some teachers.

Knowing how human behaviors develop throughout life, and how they are influenced by genetic and environmental factors, is essential for a complete comprehension of society (Wesseldijk et al., 2017), and even for the formulation of public policies, and the effective implementation of efficient educational systems (Asbury & Plomin, 2013). Finally, a bioecological analysis of the environments into which subjects are inserted permits an integrated understanding of these phenomena, as well as an understanding of how teachers’ perceptions of a determined academic behavior by their students can influence the future psychological behavior of the students, and their interpersonal relationships (Bronfenbrenner, 1996).

Since perceptions are not sufficient in themselves to plan an action about a given situation, this paper’s recommendation is to invest in continuing education courses, or to include, within possible limits, in teacher training curricula, or in already existing disciplines, studies on human behavioral genetics with cognitive and behavioral development, emphasizing behaviors that are educationally relevant.

These proposals intend to provide teachers with the framework necessary for optimizing the educational process, since, even though all behaviors are genetically influenced, an environment containing a wealth of good stimuli will have positive effects on the students’ educational performances, and will contribute to their development as fulfilled and productive citizens in society.