Tool description

The Child Eye Color Calculator is a genetics-based tool that predicts the probability distribution of a child's eye color based on the eye colors of their parents and, optionally, grandparents. Using simplified genetic inheritance models, this calculator provides percentage probabilities for brown, blue, green, hazel, and gray eye colors.

Features

  • Parent Eye Color Selection: Choose eye colors for both parents from five common options: brown, blue, green, hazel, and gray
  • Enhanced Accuracy with Grandparents: Optionally include grandparents' eye colors to account for recessive genetic traits
  • Visual Probability Distribution: Results displayed as color-coded progress bars with exact percentages
  • Genetic Context: Considers dominant and recessive alleles based on the HERC2 and OCA2 genes
  • Detailed Color Descriptions: Each predicted eye color includes shade variations (e.g., "Light blue to dark blue")
  • Multi-language Support: Available in English, Russian, French, German, and Italian

Use Cases

  • Expecting Parents: Curious parents-to-be wanting to know possible eye colors for their future child
  • Genetics Education: Teachers and students learning about Mendelian inheritance patterns
  • Family Planning: Understanding hereditary traits and genetic diversity in families
  • Scientific Curiosity: Exploring how eye color genetics work in human populations

Eye Colors Supported

  • Brown: Dark brown to light brown - dominant trait
  • Blue: Light blue to dark blue - recessive trait
  • Green: Green to olive green - intermediate trait
  • Hazel: Brown-green mixed with golden/amber flecks - intermediate trait
  • Gray: Gray to blue-gray - recessive trait

How Genetics Work

Eye color inheritance follows a multi-gene model, primarily involving:

  • HERC2 Gene: Controls OCA2 gene expression
  • OCA2 Gene: Determines melanin production in the iris
  • Dominance Hierarchy: Brown > Green/Hazel > Blue/Gray

Brown eyes are dominant, meaning if one parent has brown eyes and carries only dominant alleles, the child is highly likely to have brown eyes. However, if brown-eyed parents carry recessive alleles (often indicated by having parents with lighter eyes), children can inherit lighter eye colors.

Blue and gray eyes are recessive, requiring both parents to contribute recessive alleles for the child to have these colors.

Important Disclaimer

This calculator provides estimates based on simplified genetic models. Actual eye color inheritance is significantly more complex and can be influenced by:

  • Multiple genes (at least 16 different genes)
  • Gene interactions and epistasis
  • Rare genetic variations
  • Environmental factors during development
  • Random genetic mutations

Results are for educational and informational purposes only and should not be considered medical or scientific certainty. Real-world eye color outcomes may vary from predictions.