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A newly recognized autosomal recessive syndrome affecting neurologic function and vision
Mustafa A Salih1, Andreas Tzschach, Darren T Oystreck
1Division of Pediatric Neurology, Department of Pediatrics, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
American Journal of Medical Genetics. Part A
|May 2, 2013
Summary
A newly identified gene variant causes a rare autosomal recessive syndrome in a Saudi Arabian family, leading to intellectual disability, developmental delays, seizures, and progressive vision loss. This genetic discovery sheds light on the complex causes of congenital cognitive disturbances.
Area of Science:
- Genetics
- Neurology
- Ophthalmology
Background:
- Intellectual disability (ID) has significant genetic underpinnings.
- Consanguineous unions increase the risk of autosomal recessive disorders.
- Understanding novel genetic mutations is crucial for diagnosing rare diseases.
Observation:
- A Saudi Arabian family with consanguineous parents presented with four affected children exhibiting congenital cognitive disturbance.
- Affected individuals showed motor and cognitive delays, early-onset seizures, and varying degrees of progressive cognitive and visual decline.
- Ocular malformations and spasticity were noted in some affected children, alongside the oculodigital sign in the youngest.
Findings:
- A homozygous pathogenic variant (c.1A>G; p.Met1Val) in the previously uncharacterized C12orf57 gene was identified in all affected individuals.
- Segregation analysis confirmed the variant was heterozygous in parents and absent in unaffected individuals and a large control cohort.
- This points to C12orf57 as a novel gene implicated in an autosomal recessive neurodevelopmental and visual disorder.
Implications:
- This study identifies a new gene associated with intellectual disability and a complex syndromic presentation.
- The findings highlight the importance of genetic diagnostics in consanguineous families with unexplained developmental disorders.
- Further research into C12orf57's function is warranted to understand its role in brain and eye development.
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