Are there genes involved in hard-working or assiduity? Yeah, there is such an inherited component of variability, and it's quite large. This gene, under a slightly altered name, is one of the "big five" in the generally accepted classification of human temperament. Five complex characteristics have been identified, and they all tend to be highly heritable: extraversion, neuroticism, benevolence, openness to experience, and the one we're interested in — industriousness. Hard-working is 40 to 60 percent determined by genes, and the other half by environmental, cultural, and educational factors. That's a huge degree of inheritance, and it can have a significant impact on a person's identity.