SULEIMAN IGDOURA 370.
(photo credit: McMaster University)
Tay-Sachs disease, the degenerative and always fatal neurological genetic
disease that is most commonly carried by Ashkenazi Jews, has been recognized
even by ultra-Orthodox rabbis as a legitimate reason for the abortion of an
affected fetus. But readily available drugs called tumor necrosis factor agents
may have a “dramatic effect” on children with this condition, according to
scientists at McMaster University near Toronto.
“There is hope for this
disease,” says biology Prof. Suleiman Igdoura, lead researcher of the study.
“Imagine what that could mean for parents who have a child diagnosed with this
incurable condition, who may have only a few years with their
Tay-Sachs is a genetic disorder caused by the absence of vital
enzymes that are involved in the breakdown of waste within cells.
rare autosomal recessive genetic disorder is also known as GM2 gangliosidosis or
hexosaminidase A deficiency. Without these enzymes, waste accumulates and
eventually destroys healthy cells, leading to paralysis, blindness, mental
retardation and eventually death.
The defective gene has been carried
mostly among Ashkenazi Jews, but a different mutation affects isolated
non-Jewish French Canadians and Cajun people in Louisiana.
his team have found that when a key protein in the brain known as TNFa is
removed, some of the devastating symptoms of Tay-Sachs and a similar disease
called Sandhoff were much less severe when tested in mice. Those symptoms
include spasms, muscle wasting and loss of neurological function.
findings are significant because the protein can be managed by FDA-approved
drugs, readily available on the market, said Igdoura.
“With Tay-Sachs and
Sandhoff, we have very little to offer families in terms of therapeutics to help
their children,” said Igdoura, whose article was just published in Human
“These are orphan diseases where there are not many
medications available. But we feel this is a significant step in improving
quality of life and quite possibly extending lives,” the Canadian biologist
Prof. Ephrat Levy-Lahad, head of the medical genetics institute at
Jerusalem’s Shaare Zedek Medical Center, told The Jerusalem Post that the number
of babies actually born in Israel with Tay- Sachs is very, very small because of
pre-marital and other testing.
Most Tay-Sachs babies born in the world
are not Jewish. But when it happens, it is devastating to the family, she said,
as they usually die by the age of four or five after great
“The advantage is that TNF inhibitors already exist and are
used on various patients. If this use pans out, it will be a new pathway and be
easier to research,” said Levy-Lahad.
“It’s gratifying that researchers
haven’t given up studying Tay- Sachs, even though there are few cases because of
But if the TNF agents do nothing to protect the
Tay-Sachs baby’s brain and lungs, giving the medication would just prolong its
suffering. We wouldn’t recommend not doing termination of a pregnancy; it’s
still a clear indication for abortion. Avoiding such pregnancies are most
“There are distinct stages within the disease, so we wanted
to find targets we could interfere with, to delay the terrible outcome or halt
it altogether,” explained Igdoura.
Using mice that were genetically
altered to mimic Tay-Sachs and Sandhoff, researchers found levels of TNFa rose
significantly during the early stages of the diseases.
But when TNFa was
subsequently removed, there was a significant improvement in the lifespan of the
mice and neurological function.
“We also found that neurons didn’t die as
early as they do with the disease, so we delayed the progression as well,”
“We have identified a molecule that is the culprit and
we believe there are drugs available to stop it,” he said.