Final answer:
Parents with brown eyes can have a green-eyed child if both parents are heterozygous for the green eye trait on the green-blue eye gene. This reflects the complexity of genetic inheritance, particularly with traits influenced by multiple genes, such as human eye color.
Step-by-step explanation:
The question 'The "asian eye" (which is a genetic-based trait found in other populations also) is called .....' pertains to Biology, as it refers to genetic traits. However, I believe your question is seeking to discuss epistasis and eye color genetics rather than a specific name for a trait related to eye structure, such as 'asian eye.' Eye color in humans is determined by multiple alleles and genes that interact with each other, a concept known as epistasis.
The scenario where both parents have brown eyes and produce a green-eyed child suggests that both parents are heterozygous, having the green trait on the green-blue eye gene. This means that each parent contributes a gene for green eyes, which is recessive to brown but in combination can result in green eyes in the offspring.