Is it true that IQ of a person depends on genetics?

Yes, it is true. Genetics determine part of the IQ of an individual. IQ is greatly influenced by genetics and environmental factor. Researchers have conducted many studies to look for genes that influence intelligence.

These studies have focused on the similarities and differences noticed within family especially between identical twins, siblings and adopted children. These studies suggest that genetics determine about 50% of the differences of intelligence in individuals.

The evidence of genetic influences in IQ was demonstrated in the study of twins which showed that identical twins IQ’s are more similar than those of fraternal twins.

However, these studies are yet to conclusively identify any gene that shows the difference in intelligence.

Genetics determines part of IQ. The other part is environmental factors. Genetic factors determine about 50 percent of the difference in intelligence among individuals. Intelligence is also strongly influenced by the environment, parenting, education, availability of learning resources, and nutrition. Heritability is the genetic contribution to variance within a population and a specific environment.

The heritability of IQ increases with age and remains at that level into maturity. This happening is known as the Wilson Effect. Recent studies suggest that family and parenting characteristics are not significant contributors to variation in IQ scores. However, poor parental environment, malnutrition, and disease have a negative impact on IQ.