Researchers from Murdoch Childrens Research Institute have
developed an innovative new test that could revolutionise the way
Fragile X syndrome is screened and diagnosed.
The Murdoch Childrens test uses a DNA region that was previously
thought to have no function. Researchers say the new technology
could be used as an early detection test for both male and females,
and could be included in newborn screening tests, leading to
improved quality of life for thousands of patients and their
families.
Fragile X syndrome is a genetic disorder caused by a faulty
switch of an important gene called FMR1 which is located on the X
chromosome. Fragile X syndrome is associated with a range of
developmental, physical and behavioural problems and is the most
common known cause of inherited developmental disability
worldwide. It is estimated that 1 in 130 females and 1 in 180
males carry the FXS gene and that 12 FXS carriers and one fully
affected FXS child is born in Australia each week.
Early identification and intervention improves outcomes for
children with Fragile X syndrome but until now it has been
difficult for doctors to diagnose the disorder until the age of
three years or older.
In a world-first, the researchers have shown that the new test can
detect both the type and severity of symptoms in Fragile X syndrome
with unparalleled accuracy in DNA samples from 154 females, with 18
of these having the 'faulty switch' in the FMR1 gene.
Lead researcher, Dr David Godler, from Murdoch Childrens said that
in the study the test was shown to be superior to others available
in predicting developmental disability particularly in females, and
that the discovery could pave the way for a simple, accurate and
inexpensive test for Fragile X syndrome that could be used for
population screening.
"The test is especially advantageous for diagnosis and screening
in females, because it can specifically and accurately identify
those individuals who are expected to develop cognitive impairment
and can therefore potentially identify those most likely to benefit
from early intervention," Dr Godler said.
John Kelleher, President of the Fragile X Association of Australia
has welcomed the finding, saying the test has the potential to
benefit thousands of Fragile X patients by providing sufferers and
their families with earlier detection and intervention, leading to
better treatment and improved outcomes.
"This test has the potential to become one of the most powerful
tools to be discovered this decade for accurate diagnosis of
children with Fragile X syndrome. With it we may be able to test
and treat affected individuals earlier on in their lives giving
them the best chance to live to their full potential and to save
parents the anguish of spending years searching for a diagnosis.
The association has spent several years lobbying for the inclusion
of FXS testing within the heel prick test and now Dr Godler and his
associates have developed the technology."
The novel test was developed by Murdoch Childrens researchers Dr
David Godler and Dr Howard Slater in collaboration with Dr Danuta
Loesch from the School of Psychological Science, La Trobe
University. The work was supported by the Thrasher Research Fund
and National Health and Medical Research Council Development
grant.
Larger studies are now underway internationally to further
validate the findings. This work was published online today in the
leading clinical laboratory journal Clinical Chemistry.