https://pubmed.ncbi.nlm.nih.gov/19619260/ https://pubmed.ncbi.nlm.nih.gov/19619260/ """Nevertheless, it has been estimated that 74% of the variance in human eye

https://pubmed.ncbi.nlm.nih.gov/19619260/ https://pubmed.ncbi.nlm.nih.gov/19619260/ """Nevertheless, it has been estimated that 74% of the variance in human eye colour can be explained by one interval on chromosome 15 that contains the OCA2 gene""" That's about blue/brown, and realistically, there are a bunch of other genes which also have effects, as "eye color" is really a collection of phenotypes, not just a single one.