Gene-centered view of evolution

The gene-centered view of evolution, also known as the selfish gene theory, holds that adaptive evolution occurs through the differential survival of competing genes, increasing the allele frequency of those alleles whose phenotypic trait effects successfully promote their own propagation. The proponents of this viewpoint argue that, since heritable information is passed from generation to generation almost exclusively by DNA, natural selection and evolution are best considered from the perspective of genes.

Source: Wikipedia — Gene-centered view of evolution (CC BY-SA 4.0)