I wonder if there is a possibility of genetic constraint in the real world

Genetic constraint was a concept that appeared in science fiction or movies. It referred to the inability of two people or creatures to transform or reproduce due to genetic differences. There was currently no scientific evidence to prove the existence of the genetic constraint. The genetic variety of human beings is the result of biological evolution. There are many genetic differences between different races and species. These differences help to adapt to different environments and living conditions. These genetic differences would not have a significant impact on an individual's behavior and physiological characteristics, so the existence of a genetic lock was not in line with biological reality. Although there are genetic differences between humans, we can use scientific means to carry out genetic modification and human cloning to enhance human intelligence, physical strength and other advantages. However, these technologies are still in the laboratory stage and still need further research and verification.