Developmental delays are among the most common concerns in paediatrics and paediatric neurology practice, affecting 1–3 per cent of children worldwide. In India, studies suggest that nearly 10–15 per cent of school-aged children experience cognitive or learning difficulties, while 1 in 8 children under the age of two years show signs of developmental delay. For families, the uncertainty surrounding the cause of these delays can be deeply distressing. Early genetic testing, combined with structured genetic counselling, offers a pathway to clarity, timely intervention, and informed family planning.
Genetic Testing: Unlocking the diagnostic puzzle
Genetic testing has revolutionized the evaluation of children with unexplained developmental delays. Research indicates that 30–40% of such cases have a genetic component or risk predisposition, and with advanced technologies like chromosomal microarray (CMA) and whole exome sequencing (WES), diagnostic yields can reach up to 50%. Genetic Testing & Counselling is very important for families with children suffering from Development Delays, Intellectual Disability, Cognitive Impairment, Attention Deficit Hyperactivity Disorder, Autism & Autism Spectrum Disorders in various ways such as:
Precision medicine: Identifying a genetic etiology allows clinicians to tailor interventions. For example, metabolic disorders such as phenylketonuria or biotinidase deficiency can be treated effectively if diagnosed early.
Reducing the diagnostic odyssey: Families often undergo years of inconclusive investigations. Genetic testing provides clarity, reducing unnecessary procedures and costs.
Family implications: Many genetic conditions are inherited. Testing helps identify recurrence risks, guides reproductive choices, and enables carrier testing in parents and siblings.
In India, the rare disease burden is also significant, with an estimated 70 million individuals affected, many presenting as developmental delays in childhood. Consanguinity in certain regions further increases the prevalence of autosomal recessive disorders. Despite this, a 2024 survey revealed that the average time to diagnosis for rare genetic conditions in India is 5–7 years, highlighting the urgent need for early genetics awareness programs, enhanced genetic outreach OPDs, coupled with genetic testing.
Genetic Counselling: The human bridge between genomic science and families
While genetic testing provides answers, genetic counselling ensures those answers are understood, contextualized, and acted upon. Genetic Counselling is not merely an adjunct; it is central to the process for:
Explaining the test: Families are guided through the purpose, scope, and limitations of genetic tests, including the possibility of variants of uncertain significance (VUS).
Interpreting results: Genetic Counsellors help families understand whether findings are pathogenic, benign, or uncertain, and what this mean for the child’s health and prognosis, including the risk explanation to future pregnancies.
Psychological support: The uncertainty of genetic results can cause anxiety. Genetic Counselling provides reassurance, emphasizes ongoing monitoring, and offers coping strategies.
Family screening and prevention: Counselling highlights the importance of testing siblings or parents, and preventive surveillance such as cardiac monitoring in connective tissue disorders.
Reproductive guidance: Families are empowered to make informed choices, including prenatal testing and preimplantation genetic diagnosis (PGD), reducing recurrence risks in future pregnancies.
In India, where awareness of genetic counselling remains limited, integrating counselling into paediatric care is vital. It ensures that families are not left alone with complex genetic information but are supported in making decisions that affect both present and future generations.
What should change in routine clinical practice?
Early referral: Any child with unexplained developmental delay, intellectual disability, or multiple congenital anomalies should be referred for genetic evaluation.
Tiered testing approach: Begin with CMA for copy number variations, followed by WES or targeted panels for single-gene disorders.
Multidisciplinary care: Collaboration between paediatricians, neurologists, geneticists, and counsellors ensures holistic management.
Policy integration: India must strengthen neonatal screening and early childhood intervention programs to include genetic testing and counselling.
“In the fight against unexplained developmental delays, genetic testing and counselling are not luxuries; they are lifelines. Every child deserves the chance for an early diagnosis, every family deserves clarity, and every society must recognise that investing in genetics today secures healthier generations tomorrow.”
(The writer is a Head – CSVG, Metropolis Healthcare Ltd.)
