First published January 29, 2021.
Kalani and Jarani Dean, fraternal twin sisters from Illinois, drew worldwide attention because they were born with noticeably different skin tones.
Kalani and Jarani Dean are fraternal twin sisters born on 23 April 2016 in Quincy, Illinois, to Whitney Meyer, who is white, and Tomas Dean, who is Black. Kalani was born with very light skin and blue eyes, while Jarani has darker skin, closer to her father's. Their photos spread around the world, and their parents have said they hope the girls show that skin colour is a small difference between people who belong together.
The short scientific explanation is that fraternal twins are no more genetically alike than any other brothers or sisters, and skin colour is shaped by many genes shuffled anew for every child. Here is how that works, what the family has said, and why the twins are not members of two different races.
The Dean twins and their family
The girls' story first reached a wide audience through a TODAY feature in January 2017. Whitney described how surprised she was in the delivery room when Kalani arrived so pale that she wondered aloud whether the baby had albinism. Minutes later Jarani was born with a deeper complexion. Tomas said he first assumed newborns simply look lighter, then realised the difference was real when he saw both girls together.
The twins have an older brother, Talan, who was reported to read to them every night. The family had also lived through a loss: Whitney's son Pravyn drowned at the age of two while in day care, before the twins were born. That background gives extra weight to the way the parents talk about the girls as a gift rather than a curiosity.
Whitney summed up her view simply: "They're the same girl, just different colors." Tomas has said that what matters is love, and that he hopes people looking at his daughters will see that colour is not a big thing.
Why fraternal twins can look so different
There are two main kinds of twins. Identical twins come from a single fertilised egg that splits, so they share almost all of their DNA. Fraternal, or dizygotic, twins come from two separate eggs fertilised by two separate sperm at about the same time. They are the most common type of twin.
Because each fraternal twin comes from a different egg and sperm, they share on average about half of their genes, exactly like siblings born years apart. They can be different sexes, different heights and have different hair or eye colours. In families where parents have very different ancestry, they can also have quite different skin tones. These are sometimes called "mixed twins", and well-documented cases have been reported for decades, including a pair born in London in 1993 to a white mother and a Caribbean father.
Media reports often describe such twins as a "one in a million" event. There is no reliable statistic behind that figure. Such births are uncommon and striking, but they follow ordinary rules of inheritance.
How skin colour is inherited
Skin colour depends mainly on melanin, made by cells called melanocytes. There are two broad types: eumelanin, a brown-black pigment more abundant in darker skin, and pheomelanin, a reddish-yellow pigment. How much of each a person makes is controlled not by one gene but by many. A large recent analysis linked around 169 genes to skin colouring, including well-studied ones such as MC1R, SLC24A5, SLC45A2, OCA2 and TYR.
Every child receives one copy of each gene from each parent, and the combination is reshuffled for each pregnancy. When parents carry very different versions of these genes, the possible outcomes for their children span a wide range. Most children of a Black parent and a white parent will have a skin tone somewhere between the two, but that is a tendency, not a rule. A child can end up with mostly lighter-skin variants, or mostly darker ones, by chance.
Dr Bryce Mendelsohn, a medical geneticist at the University of California, San Francisco, explained it to TODAY with a coin-toss comparison. Flip a coin eight times and you will occasionally get eight heads. With many genes shuffling at once, unusual combinations turn up in the same way. Two such shuffles happening in twins at the same birth is what made the Dean sisters so eye-catching.
A post shared by Kalani➕Jarani Dean (@thedivadeantwins)
A post shared by Kalani➕Jarani Dean (@thedivadeantwins)
Posts from the family's Instagram account, @thedivadeantwins, show the sisters growing up side by side, sharing outfits, toys and plenty of personality.
Why the twins are not two different races
Photos of twins with contrasting skin often come with captions like "black and white twins". That framing misunderstands what race is. The US National Human Genome Research Institute describes race as a social construct used to group people, with categories that change across time and place. It also notes: "There is more genetic variation within self-identified racial groups than between them."
Skin colour is a visible trait, but it reflects only a small part of a person's genome. Kalani and Jarani have the same mother, the same father and the same family history. Differences in pigment do not divide them into separate biological groups any more than different eye colours would. Mendelsohn made a similar point: what we can see is only a thin slice of the genetic diversity every person carries.
Scientists also know that similar skin tones can evolve independently in populations far apart, as an adaptation to sunlight levels. That is one reason skin colour is a poor guide to ancestry, and a worse basis for judging anyone.
A post shared by Kalani➕Jarani Dean (@thedivadeantwins)
A post shared by Kalani➕Jarani Dean (@thedivadeantwins)
A post shared by Kalani➕Jarani Dean (@thedivadeantwins)
The family shared everyday moments online, from birthdays to matching dresses, and many followers said the photos changed how they thought about race and family.
A family message against racism
Whitney has said she hopes her daughters can be a symbol against racism and against the idea that people should be divided by colour. The twins' Instagram account, run by the family, built a large following with everyday photos of the sisters playing, dressing up and growing up together.
Stories like theirs can open a useful conversation, especially with children. A few points help keep it respectful:
- Talk about genes simply. Explain that everyone gets a mix from both parents, so brothers and sisters can look very different.
- Separate looks from worth. Skin colour says nothing about character, ability or how close a family is.
- Use the girls' names. Calling them "the white twin" and "the black twin" reduces them to a single trait.
- Let them be more than a photo. As children grow, they deserve privacy and the chance to be known for who they are.
The Dean sisters became famous for a difference, but their parents' point was the opposite: that the girls are, above all, sisters.
Sources: TODAY: Rare biracial twins surprise their parents; NHGRI: Race; Wikipedia: Human skin color; Wikipedia: Twin; photos via the family's Instagram account @thedivadeantwins; story also shared by Positive Outlooks.
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