The etiology of intelligence and learning difficulties is interpreted and perceived in different ways within society. The present study aims to explore the perceptions of a sample of n=501 Brazilian teachers regarding genetic and environmental influences on intelligence and learning difficulties. Using numerical scales, it was observed that importance was ascribed by teachers to genetic and environmental influences across both the intelligence and learning difficulties domains. For intelligence, however, the evidence points to a greater belief in genetic influence. A multiple-choice items test revealed some differences on the perceptions of teachers according to gender, age, schooling, area of knowledge, income, years of experience, knowledge of genetics, and having studied genetics. Responses favouring genetic explanations were associated with certain demographic factors while the perception that only environment affects the various domains was not associated with any specific demographics.