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Gene Therapy in Sheep May Bring Hope to Adults With Tay …

August 4th, 2016 9:35 am

For 26 years, doctors could not piece together the medical puzzle of Stewart Altman's symptoms -- as a child growing up on Long Island, he was uncoordinated and slurred his speech. Later, as a volunteer fireman, he kept falling down and had trouble climbing the ladders.

It seemed unrelated at the time, but his older sister, who had a history of psychological symptoms, was hospitalized in a mental institution. Her psychiatrist suspected a physical disorder and consulted a geneticist who eventually connected the dots.

In 1978, Altman and his sister Roslyn Vaccaro were given a stunning diagnosis: Tay-Sachs -- an inherited neurological disease that typically affects babies, killing them between the ages of 3 and 5. Only several hundred cases exist in the United States.

Altman, now 58, has a non-fatal, adult form of the disease, late onset Tay-Sachs (LOTS), and depends on his wife and a service dog to perform most daily tasks.

"I am devastated," Altman said of the disease that has robbed him of much of his speech and muscle strength, confining him to a wheelchair. "But the alternative is much worse."

His sister died in 2000 after battling LOTS-related bipolar disorder and schizophrenia -- which occurs in 50 to 60 percent of all adult cases -- and Altman and his wife raised her two sons.

Now scientists are hopeful that gene therapy may help late-onset patients like Altman and look forward to human trials.

Tay-Sachs is caused by gene mutation results in the absence or insufficient levels of the enzyme, hexosamindase A or Hex A. Without it, a fatty substance or lipids accumulates in the cells, mostly in the brain. It comes in three forms: infantile, juvenile or adult onset.

Doctors say there can be great variations in the presentation of Tay-Sachs, even in the same family with the same mutations. Babies born with Tay-Sachs appear normal at first, but by 3 or 4 years old, their nerve cells deteriorate and they eventually die. Those with LOTS can live a long life, but, like Altman, are progressively disabled.

The story of Tay-Sachs is a miraculous one. It was first identified in the late 1800s by British ophthalmologist Warren Tay and New York neurologist Bernard Sachs, who noticed the disease was prevalent in Jews of Eastern European origin.

In the 1970s and 1980s, when genetic testing became available, synagogues launched public education campaigns encouraging prospective parents to be tested, and the disease was virtually eliminated in those of Jewish ancestry.

Now, mostly non-Jews, though their risk is not as great, are among the 100 American children who have the disease, according to the National Tay-Sachs and Allied Diseases Association (NTSAD), which leads the fight for a cure.

Altman's speech is difficult to understand, so his wife Lorrie said her husband of 37 years wanted the public to know, "it's not just an infant's disease."

"Tay-Sachs is also in the general population and people don't know," she said. "He thinks we need to get the word out. One in 250 Americans carries the gene."

French Canadians, Louisiana Cajuns and even those of English-Irish ancestry have a greater chance of carrying the recessive gene that causes the disease.

Tay-Sachs is an autosomal recessive disorder, which means each parent must carry the gene. Their children have a 25 percent chance of developing Tay-Sachs, 50 percent chance of being a carrier and a 25 percent chance of being free of that recessive gene.

Altman was born in 1952, before genetic testing was available. Both his parents were carriers of the recessive gene that causes Tay-Sachs and both he and sister were stricken with the mildest form of the disease. Two of their brothers were unaffected, although one is a carrier.

The Massapequa, N.Y., couple have two healthy sons, who are carriers, but whose wives are not, and four healthy grandchildren.

For years, Altman was able to get around with a walker until he had to drop out of a clinical trial for a new drug because of debilitating side effects. After that, he said he lost 40 pounds and so much muscle that he could no longer stand on his own.

"Between the two of us we handle it and we lead kind of a normal life," said Lorrie. "But we have no idea what the future will bring."

Altman works at Nassau University Medical Center in the security monitoring department. He raises funds for about 11 different non-profit organizations, including NTSAD, and has given presentations to the Boy Scouts and senior citizens.

Much of the public work has now ended, as his speech has become more incomprehensible because the degeneration of the nerves that control his respiratory muscles.

"Stewart has a good way of just living in the moment," said his wife, who met Altman in college. "But the worst part for him is his speech. He is such a social, outgoing person."

He has faced discrimination along the way, especially after leaving a Manhattan engineering job because he couldn't climb the subway stairs.

"He has such a hard time getting a job -- it was devastating," said Lorrie Altman. "On paper, he looked so good, but his speech was terrible. He has a college degree and isn't stupid, but all people see is the wheelchair."

Doctors say that many with the milder adult form of Tay-Sachs can lead full lives, despite their disability. And science is getting closer to finding treatments for this devastating disease.

Dr. Edwin Kolodny, former department chair and now professor of neurology at New York University School of Medicine, has been a leader in the field for 30 years. He first helped identify the role of the enzyme Hex-A and later tested more than 30,000 young adults in the 1970s and 1980s.

Today, he and others are involved in the promising gene therapy studies involving first mice, then cats and now sheep. Injecting genes into the brains of Jacob lambs has doubled their life span.

Clinical trials on humans are set to begin as soon as researchers can raise another $700,000 -- in addition to a grant from the National Institutes of Health -- to manufacture the vectors required to insert the genes into the body.

"It seems like every parent in the world would like to be part of the trial," said Kolodny. "And there are reasons to think there will be success here, especially for children who have a slightly later onset and not the classic form Tay-Sachs."

In the past, infantile Tay-Sachs has seen most of the medical attention. "These children have zero quality of life," he said.

Those with mild mutations, like Altman, who have 5 to 10 percent of Hex A enzyme activity, "sometimes lead full lives," according to Kolodny. "Intellectually, most of their cognitive function is retained. We have patients who are lawyers and accountants."

Pre-conception testing is still the gold standard for fighting the disease. "If your parents don't have the same recessive genes, you are home free," he said.

Those identified as at risk for having a child with Tay-Sachs can decide to adopt or conceive through in vitro fertilization, where geneticists can test the embryos before implantation to ensure the child will be disease-free.

Doctors can also do prenatal genetic testing and if the fetus is affected, the decision is up to the parents whether or not they want to terminate the pregnancy. "Three out of four times, they are reassured they have a normal child," said Kolodny.

Doctors say such testing -- at a cost of around $100 -- should be done routinely for 18 autosomal recessive disorders, including the gene for cystic fibrosis, which occurs in one in 20 caucasians, said Kolodny. Even with advances in Tay-Sachs testing in the Jewish community, public education must continue.

"The problem is each generation forgets what happened in the prior generation -- the grandmothers die out, " said Kolodny. "We need to educate health care professionals. Each new group of students graduating from medical school isn't prepared to ask the right questions."

Susan Kahn, NTSAD's executive director, who is involved in fundraising for research, agrees that along with a fight for a cure, genetic testing is critical.

"When there is a genetic disease, it's not just about that person, there is a whole implication for the rest of the family and how they deal with it," she said.

Stewart Altman sits on the association's board of directors and is a tireless crusader for a cure.

"He's got some disabilities that make it difficult for him to do certain things, but of all the board members asking for money to support, he is probably the boldest in our group," said Kahn. "He does have a lot of limitations, but he is still very energetic and wants to do something important. Not everyone responds with the same attitude."

His wife Lorrie backed that up with a laugh. "He is persistent," she said. "He carries these little envelopes around and will ask anyone he meets for a donation. It's almost embarrassing. He's not afraid to ask."

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