The gaze of your newborn is a source of fascination and many questions for young parents. Will they keep these light eyes? Will they turn brown over the months? While genetics retains an element of magic and mystery, it now allows us to establish interesting probabilities.
Why does the colour of eyes change in infants?
At birth, the production of melanin (the pigment responsible for colouration) is very low. This is why many babies are born with blue or grey-blue eyes. During the first year, and generally until the age of 6 to 12 months, melanin production adjusts according to the genetics inherited from the parents, thus determining the final colour of the iris.
Genetics: The battle of genes
Eye colour is a complex inheritance dictated by several genes. To simplify:
Dominant genes: Brown eyes are considered dominant.
Recessive genes: Blue eyes are recessive.
This explains why two brown-eyed parents can have a blue-eyed child: they are both carriers of a "hidden" recessive gene that they passed on to their baby.
Probability Table (Estimates)
Parent Colour | Probability of Brown Eyes | Probability of Blue Eyes
|
|---|---|---|
Brown + Brown | High (approx. 75%) | Low (approx. 25%) |
Brown + Blue | Moderate (approx. 50%) | Moderate (approx. 50%) |
Blue + Blue | Very low | Very high |
When to consult an ophthalmologist for baby’s vision?
Beyond colour, your child's visual health is paramount. Regular check-ups can detect any issues early (strabismus, early myopia, etc.).
Do you have concerns about your child's visual behaviour or wish for a professional opinion?
Consult an ophthalmologist who will guide you after analysing and examining your child.