Understanding Blue Eyes: A Genetic Journey

The video explores the rarity and genetic history of blue eyes, tracing their origin to a mutation in the OCA2 gene in southeastern Europe 6,000-10,000 years ago. This mutation affects melanin production in the iris, leading to the appearance of blue eyes. Despite their rarity, blue eyes are not disappearing, as they are passed down through recessive alleles. The video also discusses how blue eyes spread through Europe and the genetic mechanisms behind eye color inheritance.

What percentage of the world's population has blue eyes?

• 50%

• 25%

• 16%

• 8%

Where did the genetic mutation for blue eyes likely originate?

• Central America

• Southeastern Europe

• Western Asia

• Northern Africa

What gene is affected by the mutation that leads to blue eyes?

• HERC2

• TYR

• OCA2

• MC1R

How do blue eyes appear blue if they lack blue pigment?

• Absorption of blue light

• Reflection of the sky

• Presence of blue cells

• Due to light scattering

What color can result if there is some yellowish pigment in the stroma?

• Blue

• Green

• Red

• Brown

Why might the blue-eyed trait have spread quickly through Europe?

• Enhanced physical strength

• Improved night vision

• Increased intelligence

• Prevented eye disorders

What type of allele is responsible for blue eyes?

• Incomplete dominant

• Co-dominant

• Dominant

• Recessive

What happens when both parents have blue eyes?

• Their children will have blue eyes

• Their children will have brown eyes

• Their children will have green eyes

• Their children will have hazel eyes

Why is the percentage of blue-eyed individuals decreasing in the western world?

• Climate change

• Global population mixing

• Increased UV exposure

• Dietary changes

What is the current status of blue-eyed individuals in the global population?

• They are a minority

• They are extinct

• They are the majority

• They are endangered