What can not influence an organisms phenotype?

Answer 1

An organism's phenotype is not influenced by genetic mutations that do not affect gene expression or protein function. Additionally, purely random genetic drift in a population does not directly alter an individual organism's phenotype. Environmental factors, while significant, can also be excluded if they do not interact with the organism's genotype. Lastly, traits that are not expressed due to recessive alleles or other forms of genetic suppression do not influence the observable phenotype.