you might think your hair and eye color arepermanent, but in reality, they could change at any time. and it definitely already changedonce. greetings programs, trace here for dnews.many babies are born with blue eyes, and then their eyes change color as their genes continueto develop. hair color is the same way, sometimes, babies are born with very light colored hairwhich gradually darkens. we got a few questions
trying different hair colors online, on this, so we did the digging! the colored part of the eye is the iris, itcontrols how much light is let into the eyeball and it's color is determined by melanin, justlike skin and hair. darker colors absorb more light, and lighter colors reflect more.
eye color is determined by a few differentgenetic factors, the most important being oca2. oca2 produced melanocytes, or melaninproducing cells. melanin is the protein that creates skin, eye, and hair color. more melaninmeans darker eyes, hair, or skin. the color of the melanin in the eyes is determined bythree other[a] genes, eycl1, 2 and 3. together, they account for brown/green/blue but nothazel or grey eyes, science is still working on how we get those. all blue-eyed peoplecan trace their ancestry back to a single human born between 6 and 10,000 years ago.due to a genetic mutation, a human was born with a tiny switch right before the oca2 gene,that limits the expression of the melanin, kind of like diluting the stream of the protein.individuals with albinism or albinos have
the oca2 gene completely shut off -- so theirskin, eyes, and hair have no melanin at all! with this in mind, let's apply it to babies.when we're born, our genetics are decided, but the body hasn't necessarily acted on allthe genes in your dna. when it comes to eye color, the melanin controlled by the oca2gene is diluted and thus we all have blue eyes. for those with that blue-eye gene mutationthey eyes stay blue. but for the vast majority of us, once we're born the oca2 gene kicksinto gear, creating melanocytes to make proteins and the eyes turn a different color, somewherebetween 9 months and two years after birth. a medium amount of the melanin makes eyesgreen or hazel, a large amount makes them brown.
with regard to hair, the melanin builds upthe same as in eyes, creating a dark color. as babies age, their melanin levels increaseand their hair will darken. hair colors can change well into puberty, as some genes aren't"switched on" until the hormones flood the body in adolescence. eventually, usually inthe 30s, human hair stops producing melanin and begins to turn grey. basically, it stopsadding color to the hair. gray hair tends to occur earlier in caucasians and later inasians. it's important to point out, that not allbabies are born with blue eyes. this mainly occurs with caucasian babies, maybe becauseof the lower levels of overall melanin due to the lighter skin tone. babies of asian,african and hispanic genetic heritages will
likely be born with dark eyes that stay dark. funnily enough, 10-15 percent of caucasiansreport their eye color continued to change into adulthood, so it's possible your peepersare still not settled!
what's your favorite eye color? what do youwish you had? tell us in the comments and make sure yousubscribe to dnews for more science! we're here twice a day, every day of the year. doyou have questions? let us know on twitter @dnews or me @tracedominguez. thanks so muchfor watching!
