Before Lori Sweazy knew that her son, Alec, had a rare medical disability, she knew he had a talent for music. The Minnetonka, Minn., mother said she noticed it when he was 3 months old, and he suddenly mimicked one of the notes she was playing on the piano. She played it again, and he mimicked it again. "I just got chills," she said.
Thirteen years later, Alec is, by all accounts, an extraordinary pianist. He can play Rachmaninoff, even though he can't read music.

Some believe his talent is a legacy of a curious disorder called Williams Syndrome, a genetic ailment that carries some heartbreaking traits - low IQ, learning disabilities, heart problems - and some joyous ones as well - outgoing personalities and a gift for language and music.

"They have a musical intelligence we are just beginning to unlock," said Howard Lenhoff, a California researcher whose 43-year-old daughter, Gloria, can barely add numbers but can sing in 25 languages.

"Most of them can't make change from a dollar," Lenhoff said. "The fact that we have winners in this population is phenomenal."

People with Williams Syndrome aren't like the autistic children who can play music but are withdrawn from the world. In fact, Williams Syndrome victims thrive in social settings.

Many parents of children with Williams Syndrome, which occurs in about 1 in 20,000 births, have long suspected their kids had a special knack for music.

But there was little scientific evidence to back up their claims. In the past few years, scientists have started studying Williams children's reactions to music, rhythm, singing, dancing and harmony. So far they've found many, though not all, have a special bond to music, if not an outright talent.

Alec can hear a simple melody once and play it from memory. Or he'll work for months on a Rachmaninoff piece and suddenly vary the mood, the timing and nuance without even realizing it.

"The way he interprets music is really extraordinary," said Joanne Scully, his piano teacher. At her home in Minneapolis he recently rehearsed "L'Orage" (The Storm) by Friedrich Burmuller, a moody piece made even more haunting by his touch.

Alec, who performed at recitals in Willmar, Minn., in April after winning a regional music competition, clearly loves being at the center of attention. With a shy smile, he confided that he liked music "that makes me rock and roll."

If he's given much thought to a future in music, it doesn't show. His goal in life? "Maybe be a train operator," he said. "Or maybe a pizza place owner."

Strange mix of symptoms

Scientists believe that Williams Syndrome is caused, at least in part, by a missing gene or missing genetic material on the seventh chromosome, which is somehow responsible for the strange mix of symptoms.

Like Alec, people with Williams often have a telltale set of "pixie-like" facial features, such as upturned nose, puffy eyes, wide mouth and small chin. They're also prone to a wide range of developmental and health problems, such as IQs in the 60s or 70s, kidney problems, hernias and heart and blood vessel disorders.

But the key to the musical mystery may lie with their hearing, which is extra-sensitive to certain frequencies and noise levels.

"Possibly that sensitivity helps them to hear the rhythms that some of us can't," said Terry Monkaba of Troy, Mich., executive director of the Williams Syndrome Association.

Lenhoff, a biochemist, discovered that his daughter, Gloria, and Alec Sweazy have perfect pitch, meaning they can identify any note, even noise from machinery.

But Alec's mother Lori is a professional violinist, so couldn't this just be a case of inherited talent?

Of course, Lenhoff said. And right now there's no proof that Williams kids have an innate musical talent.