Progress in better detection of child development problems

Posted on January 25, 2012

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Particularly important for diagnosis in girls

Two La Trobe University neuroscientists, Dr Danuta Loesch and Professor Glynda Kinsella, have played an important role in a world-first study of a new test that could revolutionise Fragile X diagnosis, paving the way for screening  new-born children for this troubling developmental disability.

The innovative test – developed at the Royal Melbourne Hospital’s Murdoch Childrens Research Institute by Dr David Godler and Dr Howard Slater in collaboration with Dr Loesch – was first reported in the journal Human Molecular Genetics in 2010.

A new study involving Dr Loesch and Professor Kinsella has now been published in the latest edition Clinical Chemistry which provides strong evidence that this test can detect both males and females affected with the Fragile X Syndrome.

‘The results,’ says Dr Loesch, ‘have created the sound basis for early application of this test for population screening, which has the potential to improve the quality of life for thousands of patients and their families, through earlier intervention and by providing information about this familial condition for better management and reproductive choices.’

She says this is particularly important for Fragile X diagnosis in girls for whom existing tests are complicated and expensive.

Fragile X Syndrome, a disorder caused by a faulty genetic ‘switch’ on the X chromosome, is the most common known cause of inherited developmental disability world-wide.

It is associated with many physical and behavioural problems including autism, where early diagnosis and intervention is particularly important. However, she says, while Fragile X is one of many genetic conditions associated with autism, the cause cannot be identified for the majority of children diagnosed with autism disorder.

Dr Loesch is a world authority on genetic research into Fragile X Syndrome. She has worked at La Trobe on many manifestations of the condition – from young children to the elderly – since the mid 1980s after relocating her research from Poland to Australia.

Dr Loesch, left, with Professor Kinsella

Discovery of gene mutation

In 1991 she helped discover that a mutation on a gene, called FMR1, was responsible for Fragile X Syndrome. This mutation, says Dr Loesch, is caused by expansion of trinucleotide (CGG) repeats. Nucleotides are the building blocks of DNA.

Fragile X research, says Dr Loesch, uses many cutting-edge and cross-disciplinary methods to learn about the nature and origin of developmental and behavioural conditions, including autism and attention-hyperactivity.

This has involved a series of genotype-phenotype relationship studies (how genes affect physical and mental condition), which formed part of the assessment of the Fragile X disorders test in the Clinical Chemistry paper.

La Trobe clinical neuropsychologist Professor Dr Glynda Kinsella has also collaborated with Dr Loesch in several earlier studies at the other end of the age spectrum, looking at brain behaviour effects of small Fragile X mutations, or ‘premutations’, which can cause problems in later life in nearly half of the people with this genetic anomaly. Another long-standing La Trobe collaborator in these studies was Dr Richard Huggins from the Department of Statistics.

Better treatment and outcomes

A former clinical neurologist turned geneticist, Dr Loesch is a regular co-researcher with leading Fragile X authority, Professor Randi Hagerman, Medical Director of the MIND Institute at the University of California, Davis.

Professor Hagerman is on the record as advising the US House of Representatives Subcommittee on Health and Environment that ‘Fragile X represents a portal through which we hope to view and treat a wide variety of other disorders of brain development and function. All children with autism…should be tested for Fragile X.’ The new diagnostic test could bring that goal a step closer.

In the official announcement of the research findings, President of the Fragile X Association of Australia, John Kelleher, said the test could lead to better treatment and improved outcomes

‘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.’

● La Trobe University is also home to the Olga Tennison Autism Research Centre (OTARC)  Australia’s first centre dedicated to research into Autism Spectrum Disorders.

Headed by developmental psychologist Dr Cheryl Dissanayake, it helps advance knowledge of the nature and causes of Autism Spectrum Disorders, and develops evidence-based strategies for supporting individuals and families.

See also: ‘Look here! Research toward earlier autism diagnosis’