Neurogenetic Disorders in Children: Diagnosis and Care

When is a genetic cause considered?

A genetic evaluation is considered when a child has developmental delay or intellectual disability without a clear cause, epilepsy starting early in life, very low or high muscle tone, loss of skills, unusual facial features or body proportions, or skin markings such as several light-brown patches or pale patches.

A similar condition in a brother, sister or other relative, or parents who are related by blood, also makes a genetic cause more likely.

Which conditions are neurogenetic disorders?

Neurogenetic disorders include chromosomal conditions such as Down syndrome, conditions such as fragile X syndrome and Rett syndrome, neuromuscular conditions such as Duchenne muscular dystrophy and spinal muscular atrophy, and neurocutaneous conditions such as tuberous sclerosis and neurofibromatosis. Many rarer conditions affect brain development or metabolism.

Each is uncommon on its own, but together they explain a sizeable share of developmental and seizure problems in children.

How does genetic testing work?

Testing usually needs a blood sample from the child, and sometimes from the parents. Depending on the question, it may look at the chromosomes as a whole, at a single gene, or at many genes at once. Results can take several weeks.

Before testing, the family is told what the test can and cannot find, what a result might mean, and what happens next. Some results are clear; others need careful interpretation, and genetic counselling is arranged where it helps.

Why does a genetic diagnosis matter?

For some conditions, specific treatment now exists and works best when started early. For others, a diagnosis guides which problems to watch for, such as heart, eye or hearing issues, and stops the search for a cause through repeated tests.

A diagnosis also tells the family whether the condition could recur in a future pregnancy, and connects them with others facing the same condition.

Frequently asked questions