THE SCIENCE OF CLEFT LIP AND PALATE
AROUND 1 IN 700 CHILDREN ARE BORN WITH THE BIRTH DEFECT EACH YEAR. HERE’S WHAT YOU NEED TO KNOW ABOUT HOW CLEFTS FORM, WHAT CAUSES THEM AND HOW THEY CAN BE REPAIRED.
WHEN I WAS BORN,
two tiny gaps — no more than a few millimeters across — split apart my upper lip and the roof of my mouth. My parents had known about this craniofacial anomaly at least several weeks before my birth, thanks to a routine ultrasound. Over the course of the next few decades, I would undergo countless surgeries, from complicated orthodontic procedures to jaw-breaking bone grafts.
My experience is hardly unique. One in 700 to 1,000 babies are born with either (or both) a cleft lip and/or cleft palate, which occurs when the lip or mouth doesn’t properly fuse during early pregnancy. “Cleft lip and palate is one of the most common congenital birth defects,” says Janice Lee, clinical director of the Craniofacial Anomalies and Regeneration Section of the National Institute of Dental and Craniofacial Research. “It’s a separation in the lip and nose, and in the palate. And there’s a gap between the mouth and the nose.”
This seemingly small gap can cause big problems. For starters, says Lee, it can pose issues with feeding, as babies born with clefts aren’t able to form a seal with their mouths. Speech difficulties can also arise, since the palate is crucial in forming certain sounds. And some may struggle with stigmatization from others due to such a visible facial difference, particularly in lower-resource communities where surgery isn’t always an option.
Despite their prevalence, there’s plenty that people don’t know about clefts. “A lot of people don’t know how common they are,” says Brent Collett, a pediatric psychologist at Seattle Children’s Research Institute who studies young children with craniofacial conditions. “There are a lot of babies who are affected by this.”
DURING THE EARLY
stages of pregnancy — when an embryo is no larger than a grain of rice — both body tissue and specialized cells from each side of the head grow towards the center until they join together. “Facial development occurs at six weeks in utero,” says Lee. This fusion forms our facial features, like the lips, nose and mouth. (In this sense, everyone starts out with a cleft lip and palate.) But when those tissues don’t fuse, it can result in a cleft lip, when the upper lip doesn’t form properly, and/or cleft palate, when the roof of the mouth doesn’t close.
Clefts have likely been around for a long time; King Tutankhamun, for instance, suffered from a partial cleft palate. Throughout history and across
cultures, many have tried to suss out what, exactly, causes their occurrence. One theory among traditional Hindu and Muslim healers posits that if a pregnant woman carries a sharp object during an eclipse, her infant could be born with a cleft. Even today, some cultures view the condition as divine punishment for parental sins.
But scientists still don’t know precisely what leads to clefts. Most researchers believe that they’re caused by a cocktail of genetic and environmental factors. “A lot of things can cause it,” says Lee, who adds that scientists are continuously identifying new genes that may be associated with clefts. In a 2019 study published in Science Advances, researchers identified more than
100 new genes that could lead to the development of cleft lip and palate.
Environmental factors likely play a role, too. Scientists know that smoking, diabetes and certain medicines used to treat epilepsy can boost a parent’s risk of having a baby with a cleft.
THERE’S NO
“one-size-fits-all” approach when it comes to repairing clefts. Still, Lee says that in the U.S., the surgical trajectory is pretty consistent. “Most babies will have their cleft lip repaired first, and that allows them to [make a] seal properly, and that continues before the baby is six months old,” she says. “And then the baby will undergo cleft palate repair, usually around a year old; you want them to have that seal in the palate so there isn’t air escaping between the palate and the nose.” As the child grows, they’ll typically undergo a series of orthodontic treatments, and may need additional surgeries, as well. Some adults born with a cleft have had more than 10 operations on their mouth, nose and jaw throughout their life.
Those years of intensive procedures add up — total lifetime treatment costs can range from $100,000 to $200,000 per person. Plus, beyond the needs of surgical care, individuals with clefts may also have an increased risk for certain diseases like breast and lung cancer, and tend to experience more learning difficulties as young children.
Even when facing these hurdles, with treatment, most children with clefts are able to lead happy and healthy lives. “Having a congenital birth defect really doesn’t define you,” says Lee. “That’s so important for families to know and feel; there are teams that want to support the whole family. And we hope that there are noninvasive therapies in the future so that kids don’t have to go through multiple surgeries.”
For cleft patients who have had scores of surgeries throughout their lives, it’s important to remember that each treatment represents another step in a longer journey. A few years ago, I was delighted to get new prosthetic front teeth after a major surgical repair the previous summer. Before, like many with clefts, I sometimes smiled without showing my teeth. Now, I’m much more likely to flash a toothy grin whenever someone pulls out a camera.
Researchers identified more than 100 new genes that could lead to the development of cleft lip and palate.