Authors: Galia Baalbaki , Hajira Karim , Lima Oria , Muhsin Elmas ,

Abstract

Background: Spastic ataxia type 5 (SPAX5) is a rare autosomal recessive neurodegenerative disorder that is
characterized by a progressive combination of spasticity, cerebellar ataxia, and difficulties with fine motor
coordination. This report aims to highlight the clinical profile, diagnostic findings, and genetic aspects of
SPAX5, emphasizing the value of Whole-exome sequencing in diagnosing rare hereditary disorders.

Case Presentation: In this report, we present the clinical progression, findings, and genetic classification of a
47-year-old male diagnosed with spastic ataxia type 5, who, over the past decade, has experienced worsening
balance instability, weakness, and increasing walking disturbances. Upon follow-up, he presented with gaze
palsy and a noticeable decline in cognitive function. Family history noted a cousin aged 60 with similar symptoms, consistent with the autosomal recessive inheritance pattern characteristic of SCA5. Genetic analysis: Whole exome sequencing (WES) revealed a homozygous likely pathogenic variant in the AFG3L2 gene, confirming the diagnosis of SPAX5. This discovery emphasizes the genetic etiology of the disease and underscores the role of familial inheritance in its pathogenesis and progression.

Conclusion: This case stresses the value of genetic testing, particularly WES, in diagnosing disorders like SPAX5, which often present with nonspecific clinical manifestations and overlap with other neurodegenerative disorders. It also further illustrates the importance of community-based genetic studies to better understand the inheritance patterns of rare hereditary disorders and to enhance management strategies.

Keywords: Spastic Ataxia Type 5, Autosomal Recessive Inheritance, AFG3L2 gene, Neurodegenerative disorder, Whole Exome Sequencing, case report.