Beautiful Mystery : They struggle to tie their shoes and make change. But they can master music and languages. It’s all part of the Williams syndrome riddle.

Twenty-nine years ago, a doctor at a Denver mental hospital sat a sickly, slightly retarded boy named Tim Baley down at a piano and watched him run his fingers across the ledges and valleys of the keyboard.

The puzzled doctor began jotting down notes. Baley had undergone hundreds of tests, but medical minds were still having a hard time coming up with a diagnosis for the boy’s developmental problems and poor health.

The piano test only deepened the mystery. Most kids who came through the ward, the ones with Down’s syndrome or autism, would gleefully crash their palms down on the keys. Not Baley. “The doctor told us Tim was fascinated by it,” Baley’s father recalled, “and they said we should try to encourage him.”

It probably would have been hard to discourage him. Baley, now 42 and living in Anaheim, has became a polished concert pianist who has performed in nine countries. He can’t drive, he can’t make change for a dollar, nor can he read the music he plays so artfully, but his breathtaking abilities regularly bring audiences to their feet.

Tim Baley’s story would be an incredible one if he were unique, but it is even more compelling to realize, as doctors have in recent years, that he is not one of a kind at all. In fact, last month Baley stood on a San Diego stage with four other Orange County musicians who share his unusual mix of profound ability and disability.

Baley and his band-mates have Williams syndrome (WS), a rare congenital disorder that has bolted from obscurity in the past few years to offer scientists a tantalizing riddle about the workings of the human mind. How can the condition stunt most learning and intelligence but leave other complex skills, such as verbal abilities, unscathed or, seemingly, even enriched?

“It is a beautiful mystery, just beautiful,” said Ursula Bellugi, director of cognitive neuroscience at the Salk Institute in La Jolla. “There is an exciting possibility here.”

Baley shrugs when asked about the unusual nature of his talents. “I’m not handicapped,” he told a reporter, wagging his hands in the air. “I have all my fingers.”

*

The debut performance of Baley’s band, the Williams 5, was at a national convention of the Williams Syndrome Assn., a group that has grown from 150 families to 2,500 in less than a decade. The mood at the event was celebratory, and it was clear that the group’s members are enthusiastic about the increasing attention WS is receiving from researchers.

“This whole thing is about to blow wide open,” said UC Irvine biology professor Howard Lenhoff, whose daughter, Gloria, has WS and performs with the Williams 5. “The mystery of this syndrome is being solved.”

The syndrome was named for J.C.P. Williams, a physician who in 1961 thought it was unusual that four infants in his care displayed a mild retardation coupled with a heart defect. Williams, then on staff at the Green Lane Hospital in New Zealand, typed up a paper, but his findings went largely unnoticed.

Thirty-two years later, geneticists at the University of Utah studying heart defects made the next major WS discovery when they happened upon the cause of the mysterious syndrome. Their findings, which tie WS to a missing chunk of DNA material in chromosome 7, touched off a flurry of scientific interest in the birth disorder.

The Utah researchers found that people with WS are missing a gene responsible for manufacturing elastin, a protein that allows the body’s tissues to flex and recoil. This would seem to be the culprit behind the heart ailments and other tissue problems that plague people with WS. Also missing are some genes of unknown purpose that surround the elastin agent, creating blank spots on the body’s genetic map.

These blank spots are intriguing, Bellugi said, because they are likely tied to the unusual WS cognitive development.

“The elastin-producing gene nicely accounts for many of the physical manifestations, such as the heart problems and maybe the facial traits, but we still have to map out the rest of the missing genes,” Bellugi said. “That is where the potential for discovery lies.”

Bellugi and a team of specialists at Salk are focusing on how and why people with WS have their language and social skills spared even though their condition causes malformations throughout the brain. How can a WS child weave an outlandish and vivid make-believe tale, complete with complex grammar and creative word choice, but not be able to tie his shoes?

*

The answer, if found, could shed light on the theory that language is somehow separated from other functions of the mind.

Seeking data, Bellugi and her colleagues compared children with WS to youngsters who have the same IQ but were born with Down’s syndrome. The two groups were about even in their lack of problem-solving abilities, but when asked to name as many animals as they could in 60 seconds, the groups gave markedly different responses.

The Down’s children named the animals a first-grader might, such as dogs, cats and horses, while the WS subjects rattled off obscure or exotic creatures, such as weasels, newts, salamanders, Chihuahuas, ibexes and yaks. People with WS also show a startling ability to remember faces, far better than most “normal” people, which complements their tendency to be highly sociable and friendly.

For Lenhoff, whose daughter, Gloria, can speak six languages and sing opera, the stunning dichotomy of skills among WS subjects defies any easy categorizing.

“How can we really say they are retarded or developmentally disabled?” Lenhoff asked. “In many ways, some of these Williams kids are superior to a lot of typical people in verbal skills or music. I say the best thing to call them is mentally asymmetric. They are different, really, not disabled.”

*

During the Williams 5’s raucous debut performance, a parent of one of the performers scanned the faces of the exuberant, dancing crowd of children bunched up near the stage. “They all look related, they all look like they could be family,” she sighed.

People with WS, especially when they are younger, share elfin features, with almond-shaped eyes, wide mouths beneath small, upturned noses and oval ears. One out of every 20,000 infants is born with Williams. Most will have a heart murmur and a narrowing of the arteries, leading to coronary ailments that can range from minor to life-threatening.

The Williams babies also often suffer severe gastric problems and slow growth. Many parents must cope with their children’s sleeplessness and irritability, conditions doctors say are probably tied to high calcium levels.

As they grow older, youngsters with Williams show delayed physical and mental development. Many of the childhood medical ailments, except for the gastric problems, tend to tail off, but muscle and skeletal maladies often set in.

People with WS also share a love of conversation (parents among the WS circles call it a “cocktail personality”) and of music that goes far beyond the hyper-chattiness and love of song found in most all children.

As the Williams 5 wound their way through a set that included “The Rose” and “Take Me Home, Country Roads,” their younger counterparts at the foot of the stage would alternately dance wildly and stare intently at the performers, seemingly transfixed by the melody and rhythm.

Lenhoff is eager for the scientific testing, which has so far dwelt on language abilities, to venture into the group’s affinity for music.

“I can’t wait,” he said. “It is the aspect that fascinates me most. I’m sure my daughter is part of the reason for that. But I also think the connection with music is what makes Williams so different.”

His daughter, the soprano in the Williams 5, is an accomplished stage performer who has toured concert halls around the world. She has perfect pitch, as do most people with WS, and she has the hyper-sensitivity to sound, called hyperacusis, that comes with the condition.

“I can hear dog whistles,” Gloria, 39, confides with a grin. “But loud noises, I hate loud noises. They scare me and I just . . . lose it.”

*

The link might be cultivated and highlighted by a new music camp for youngsters and adults being offered by the Williams Syndrome Assn. at Tanglewood, the performing arts facility in Massachusetts. The camp debuted last weekend with a program for 40 students that included voice, musical theater, piano and a variety of recreational activities.

“It’s really just the start of something bigger, I hope,” said Lenhoff, who helped organize the camp and whose daughter is attending.

“Someday I hope, we all hope, to have a residential music and arts college.”

The Williams 5 are finished with their set and an Elvis impersonator is onstage at the Bahia Hotel convention room, delighting the room full of dancing children with a hip-shaking rendition of “C C Rider.” Gloria, smiling, is watching the faces on the packed dance floor and trying to answer a hard question.

“What would I do without music? I don’t know. I can’t live without it.” Her brows knit in an effort to imagine the world without the one thing, sometimes the only thing, that makes complete sense to her. “No songs? It would be . . . torment. Just torment.”

Gloria asks for another question, hoping to do better this time. What is your secret wish? “Well, I have always wanted to go on Wheel of Fortune,” she says, but then changes her mind.

“I would want people to understand us,” she says. “If people could see what we can do, all of us, what we can do as a person, then they would call us what we really are. Mentally gifted.”