Genetics as the Foundation of Modern Medicine: New Opportunities for Treating Children with Developmental Delays

Modern medical genetics is rapidly advancing, opening new possibilities not only for diagnosing but also for treating a range of rare and complex diseases. Conditions once considered irreversible or "untreatable" 10–15 years ago can now be managed thanks to advancements in molecular medicine, genetic therapy, and targeted treatments.

One critical area is supporting children with psychomotor or speech developmental delays caused by genetic factors. Identifying a precise molecular diagnosis not only improves understanding of the disease’s pathogenesis but, in some cases, enables the prescription of specific therapies.

Examples of conditions with developmental delays that have established or promising treatments include:

• Spinal Muscular Atrophy (SMA): Gene therapy (Zolgensma), antisense oligonucleotides (Spinraza), and splicing modulators (Evrysdi) transform the disease prognosis, preserving motor functions from early infancy.
• Tuberous Sclerosis: For this syndrome, associated with developmental delays and epilepsy, everolimus, an mTOR pathway inhibitor, is used.
• Phenylketonuria: Early detection and dietary management or enzyme replacement therapy can completely prevent cognitive impairments.
• Syndromes associated with epileptic encephalopathies (SCN1A, CDKL5, STXBP1): Access to targeted anticonvulsants or experimental molecules in clinical trials.
• Cystic Fibrosis, Gaucher Disease, Fabry Disease: Examples of hereditary diseases where specific therapies significantly improve quality of life, reduce organ damage, and support cognitive development.

Genetic diagnostics now serves not only for prognosis or diagnosis confirmation but is key to prescribing personalized therapies—from dietary interventions to innovative gene therapies.

Thus, genetics is not standing still, offering real opportunities for children with developmental disorders to receive previously inaccessible help. Timely diagnosis, a multidisciplinary approach, and access to international therapeutic protocols enable the development of a high-quality medical care model for these children in Ukraine.

I. Metabolic and Enzymatic Disorders (Lysosomal Storage Diseases)

Condition	Gene	Treatment
Gaucher Disease	GBA	Imiglucerase, velaglucerase (ERT), miglustat
Fabry Disease	GLA	Agalsidase, migalastat (first pharmacological chaperone)
Pompe Disease	GAA	Alglucosidase alfa (Myozyme)
Mucolipidosis	GNPTAB, others	Supportive therapy, experimental ERT
Niemann-Pick Disease Type C	NPC1, NPC2	Miglustat, supportive
Mucopolysaccharidoses (I–VI)	IDUA, IDS, others	Enzyme replacement therapy (Aldurazyme, Elaprase)

II. Neurogenetic and Motor Disorders

Condition	Gene	Treatment
Spinal Muscular Atrophy (SMA)	SMN1	Spinraza, Zolgensma, Evrysdi
Wilson Disease	ATP7B	D-penicillamine, trientine, zinc
Lesch-Nyhan Syndrome	HPRT1	Allopurinol, behavioral support
Huntington’s Disease	HTT	Clinical trials of antisense therapy (IONIS-HTT)

III. Epileptic Encephalopathies with Targeted Therapy

Condition	Gene	Treatment
Dravet Syndrome	SCN1A	Clobazam, stiripentol, Epidiolex (cannabinoid)
Lennox-Gastaut Syndrome	Various	Epidiolex, felbamate
Tuberous Sclerosis	TSC1/TSC2	Everolimus (mTOR inhibitor)
CDKL5 Syndrome	CDKL5	Experimental gene therapy, supportive

IV. Hematological Genetic Disorders

Condition	Gene	Treatment
Beta-Thalassemia	HBB	HSCT, Zynteglo (gene therapy), lentivirus
Sickle Cell Anemia	HBB	HSCT, Casgevy (CRISPR-Cas9 genome editing)
Congenital Hypofibrinogenemia	FGA, FGB	Fibrinogen replacement
Hemophilia A / B	F8, F9	Etranacogene dezaparvovec (gene therapy form of factor IX)

V. Growth and Sexual Development Disorders

Condition	Gene	Treatment
Achondroplasia	FGFR3	Vosoritide – CNP analogs
Prader-Willi Syndrome	15q11-q13	Growth hormone, behavioral therapy
Turner Syndrome	Monogenic/X-chrom.	Growth hormone, estrogen replacement therapy
Congenital Adrenal Hyperplasia	CYP21A2	Glucocorticoids, sex hormones

VI. Immune System Disorders (Monogenic Immunodeficiencies)

Condition	Gene	Treatment
SCID (Severe Combined Immunodeficiency)	IL2RG, ADA	HSCT, Strimvelis (gene therapy for ADA-SCID)
X-linked Agammaglobulinemia	BTK	IgG replacement therapy
Chronic Granulomatous Disease	CYBB	HSCT, gene therapy in development

VII. Rare Syndromes with Potential Pathogenetic Therapy

Syndrome	Gene	Treatment
Angelman Syndrome	UBE3A	Experimental antisense therapies (ASO)
Rett Syndrome	MECP2	Symptomatic, gene therapy in clinical trials
Behçet’s Disease	MEFV, polygenic	Colchicine, biologics

Conclusions

As of 2024–2025, over 50 genetic diseases have proven treatments, with dozens more in the final stages of clinical trials. Treatments include:

• Enzyme replacement therapy
• Gene therapy (AAV, lentivirus, CRISPR)
• Molecularly targeted drugs (antisense oligonucleotides, chaperones)
• Hormonal or replacement support

This provides a realistic prospect for establishing clinical pathways in early diagnosis and treatment programs.

Every expert genetic test at our Center is accompanied by free counseling by a geneticist to explain the results.