Axis Journal of Medical and Biosocial Sciences (AJMBS)

PREVALENCE OF MITOCHONDRIAL DNA MUTATIONS IN YOUNG ADULTS WITH UNEXPLAINED NEURODEGENERATIVE SYMPTOMS

Authors

  • Athar Mahmood

    Author

  • Hafiz Niamat Ullah

    Author

Keywords:
Genetic Testing; Mitochondrial DNA; Mutation; Neurodegenerative Diseases; Pakistan; Prevalence; Young Adult
Abstract

Background: Unexplained neurodegenerative symptoms in young adults often present a diagnostic challenge, with mitochondrial DNA (mtDNA) mutations increasingly recognized as a potential underlying cause. Despite global evidence of mitochondrial dysfunction in neurological disease, prevalence estimates in South Asian populations remain limited.

Objective: To investigate the prevalence of pathogenic mtDNA mutations among young adults with unexplained neurodegenerative conditions and to assess their clinical associations.

Methods: A cross-sectional study was conducted in Islamabad over five months, enrolling 216 adults aged 18–40 years who presented with progressive neurological symptoms without established etiology. Clinical data were collected using structured assessments, including the Mini-Mental State Examination (MMSE) and Unified Parkinson’s Disease Rating Scale (UPDRS). Peripheral blood samples were analyzed using next-generation sequencing to identify pathogenic or likely pathogenic mtDNA mutations. Statistical analyses included chi-square tests, independent t-tests, and logistic regression.

Results: Pathogenic mtDNA mutations were identified in 47 participants, representing a prevalence of 21.8%. The majority of mutations involved complex I genes (59.6%), followed by complex IV genes (25.5%) and mitochondrial tRNA mutations (14.9%). Mutation carriers had a significantly earlier mean age of symptom onset (26.8 ± 4.9 years vs. 30.3 ± 5.6 years, p = 0.001) and displayed more severe impairment with lower MMSE scores (23.6 ± 4.8 vs. 26.9 ± 3.7) and higher UPDRS scores (27.4 ± 10.3 vs. 19.2 ± 8.5). Logistic regression showed that a positive family history was independently associated with mutation carriage (OR 2.36, 95% CI 1.21–4.61, p = 0.011).

Conclusion: Mitochondrial DNA mutations were present in more than one-fifth of young adults with unexplained neurodegenerative symptoms and were linked to earlier onset and greater clinical severity. Routine mtDNA testing should be considered in such patients to enhance diagnostic accuracy.

Author Biographies
  1. Athar Mahmood

    Assistant Professor Urology Services Institute of Medical Sciences Lahore, Pakistan.

  2. Hafiz Niamat Ullah

    Associate Professor General Surgery Department, Lady Reading Hospital Peshawar, Pakistan.

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Axis Journal of Medical and Biosocial Sciences
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Published
2025-11-30
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Vol. 2 No. 2 (2025): Axis Journal of Medical and Biosocial Sciences (AJMBS)
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Articles
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Copyright (c) 2025 Athar Mahmood, Hafiz Niamat Ullah (Author)

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PREVALENCE OF MITOCHONDRIAL DNA MUTATIONS IN YOUNG ADULTS WITH UNEXPLAINED NEURODEGENERATIVE SYMPTOMS. (2025). Axis Journal of Medical and Biosocial Sciences, 2(2), 42-53. https://axisjmbs.com/index.php/home/article/view/29