Joey Moretti loves to open doors. And this one gives way to the Cell and Genome Sciences Building, a glassy hive of labs and offices in the UConn Health corridor in Farmington, Conn. It’s the last day of March. The wind blows helixes of leaves into the sky. Joey, who is 4, is here because Stormy Chamberlain invited him, along with a dozen other children and their families, to tour the works.

And so begins three hours of cheerful pandemonium. Some kids tool around touching everything, their parents exerting mild but practiced vigilance. Others lean from their strollers. As Chamberlain bumps the group erratically forward, her blonde ponytail lifting as she kicks up speed, she points out various sights: centrifuges, pipettes, microscopes, trays of cell cultures. She and her four graduate student assistants also answer these parents’ informed questions. Words cut through the commotion: neuron, deletion, imprinting, RNA.

Chamberlain is an assistant professor of genetics and genome sciences. And, it’s fair to say, she’s a big deal: The day before this tour, she was named one of the “nine best female scientists you should know” by the website Fiat Physica. She’s a graduate of Princeton. She’s worked at some of the top genetics labs in the country. She’s won prestigious awards for both her teaching and her research. But this 40-year-old mother of two hardly stands on ceremony. Indeed, she had to scare up a white lab coat for the occasion, and when asked if she has any hobbies, she jokes they are (1) “running, then drinking beer” and (2) “yelling at my kids — and I’m getting better at it.”

There’s another reason Chamberlain is at home with today’s tumult: she comes from a big ranching family in Wyoming, and has been on plenty of cattle drives. So she’s perfectly fine when Joey, smiling broadly, adores doors. Click, thwack, go the metal lab doors. Bang, bang, BANG, goes the janitor’s closet. “Opening and closing doors, that’s a big accomplishment for Joey,” explains his dad, Joe, who oversees his son’s labors while also corralling two-year-old Luca, Joey’s little brother.

Joe Moretti is VP of operations at The Edge Fitness Club, but these last few years he’s become something of an amateur geneticist. As the doors whoosh and clang, he strains to hear Chamberlain describe her team’s latest research. It concerns Angelman syndrome, the chromosomal abnormality Joey and all these kids share.

Harry Angelman was a British pediatrician who, in 1965, noticed that three similarly disabled children were admitted to his ward at the same time, “purely by chance,” as he wrote decades later. Each had a jerky gait, a large mouth and widely spaced teeth, almost no speech, and excessive laughter. Angelman wrote a paper on the children, which fell into obscurity until the 1980s, when the disability began to be studied in earnest. Since then, scientists have learned that Angelman syndrome is a rare neurogenetic condition that occurs in 1 in 15,000 live births. It results from a problem with a single gene called UBE3A that lies on the 15th chromosome inherited from the mother.

Angelman syndrome causes severe cognitive delays, seizures, and impaired bodily coordination. Most of the children visiting today walk with a hitch. Some can’t walk without assistance. Most speak fewer than 50 words. None is likely to ever live independently.

But this chromosomal malfunction, for reasons yet unknown, also produces a surprisingly sunny disposition. Angelman kids — often, understandably, called “angels”— smile and laugh a great deal. The Scottish poet Richard Price has a daughter with Angelman syndrome, and in his poem “Hand Held” he writes, “We are champions of grin.”

Or as Joey’s mother Tai puts it, “Joey makes you feel you have to be happy — because he is.”

That’s the unexpected thing, maybe — that happiness is the presiding emotion at the lab today. This doesn’t discount the exhaustion the families feel over the challenges of raising disabled children. Nor the frustration the researchers feel, even if they’re getting closer to understanding what causes Angelman — and how gene therapies may reduce its effects in the coming decade. It’s just that the kids are so endearing. And the parents are so tolerant.

“These lab tours are such a great chance to connect with the other families and meet the researchers,” says Bob Dell. “This really fosters team-building and a sense of community.” Dell manages to eke out these full sentences while his son, 9-year-old Gabriel, enfolds him like an octopus. “He likes to use my ears as handles,” Dell says, smiling. Over in the lunchroom, Katie DeLucia, age 13, in a blue flowered dress, is half teaching the recently viral “Whip Nae Nae” song to graduate student Judy Bloom. Twirling, stumbling, giggling ensues.

In between these dance sessions, Bloom presents her own area of research to the families. It focuses on how Angelman neurons “talk” to each other. Picture a neuron as sort of a mushroom with nubs on it, she says. There are fewer nubs on the Angelman neurons than on typical neurons. “My hypothesis is that those fewer nubs cause problems with communication,” she explains. So she’s creating mathematical models to figure out how, and how much, the neurons signal each other.

Down the hall, Chamberlain helps Joey climb onto her lab swivel chair so he can make the world spin.