Genome wide association studies use "phenes" or "traits" (symptoms) to distinguish groups in the human population.
On the contrary the results of these studies implicate a large number of gene alleles that have a very small effect (phene).
In general it takes a combination of particular genes, environmental influences and random variation to give rise to any one phene in an organism.
However, if one defines "genes" as "DNA sequences encoding polypeptides", they are not directly accessible to natural selection; the associated phenes are.
Note that some, e.g. Richard Dawkins, have used a wider definition of "gene" than the one used in genetics on occasion, extending it to any DNA sequence with a function.
Compare a (fictional) kind of mutation that breaks the DNA strand in a crucial position and defies all attempts to repair it, leading to cell death.
[4] It is a valuable concept in the genomic era where "phenes" or "traits" (symptoms) are used to distinguish groups with genetic disorders.
"Phene" is used as to refer to relevant phenotypic traits in the OMIA (Online Mendelian Inheritance in Animals) database.