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In Vitro Modeling of Down Syndrome Neurogenesis Using Human-Induced Pluripotent Stem Cells

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A Rare Genetic Intersection: Down Syndrome With Coexisting Spinal Muscular Atrophy.

Bhavna Gupta¹, Madiha Mohamed², Aman Sohal^3,4

¹Department of Pediatrics/Specialist Pediatrics, Al Qassimi Women's and Children's Hospital, Sharjah, ARE.

|September 20, 2024

Summary

This case report highlights a rare instance of Down syndrome (DS) co-occurring with spinal muscular atrophy (SMA) in an infant. Early diagnosis and vigilance are crucial for managing these complex co-existing genetic conditions.

Keywords:

down syndrome genetic disorder pediatric neurology pediatrics spinal muscular atrophy

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Area of Science:

Genetics
Pediatrics
Neurology

Background:

Down syndrome (DS) is a chromosomal disorder, while spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder.
The co-occurrence of DS and SMA is exceptionally rare, presenting unique clinical and diagnostic challenges.

Observation:

A three-month-old infant presented with respiratory failure, initially diagnosed with DS based on clinical features and chromosomal analysis.
Recurrent infections and extubation difficulties prompted further investigation, revealing a homozygous pathogenic mutation for SMA type 1 via whole exome sequencing.

Findings:

The case demonstrates the diagnostic complexity arising from overlapping symptoms like hypotonia and motor delays in both DS and SMA.
Whole exome sequencing was critical in identifying the co-existing SMA diagnosis.

Implications:

This report emphasizes the need for comprehensive genetic evaluation in infants with syndromic features and overlapping symptoms.
Clinicians require heightened awareness for rare co-occurring genetic conditions to ensure appropriate management, counseling, and improved patient outcomes.