Comprehensive Mitochondrial Genome Analysis
- Mitochondria play a critical role in essential cellular functions including energy generation and many cellular pathways. Mutations of the mitochondrial genome (mtDNA) can lead to mitochondrial dysfunction and cause disorders.
- Mitochondrial disorders are clinically heterogeneous with variability of clinical presentation, age of onset, course of disease and genetic etiologies. Some mitochondrial disorders only affect a single organ, but most involve multiple organ systems, particularly, those where the cells have high energy demands, such as brain, skeletal muscles, heart, eyes and the endocrine system. Clinical features of mitochondrial disease include developmental delay, seizures, sensorineural deafness, optic atrophy, pigmentary retinopathy, ptosis, external ophthalmoplegia, myopathy, exercise intolerance, cardiomyopathy, diabetes mellitus, stroke-like episodes and others. Some conditions are mainly caused by mtDNA deletion such as Kearns-Sayre syndrome (KSS), chronic progressive external ophthalmoplegia (CPEO), and Pearson syndrome. Others are more likely associated with single nucleotide changes, such as mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS), myoclonic epilepsy with ragged-red fibers (MERRF), neurogenic weakness with ataxia and retinitis pigmentosa (NARP), or Leigh syndrome (LS). Mitochondrial disorders can be caused by mutation in mtDNA or nuclear DNA (nDNA).
- Mitochondrial disorders caused by mutations in mtDNA are estimated to be as frequent as 1/5000. When a mutation is located in mtDNA, the condition is maternally inherited. When mutant and wild-type mtDNA co-exist (heteroplasmy), it is very important to determine the percentage of the mutant mtDNA since the severity of disease is related with the level of heteroplasmy.
- Genetic testing can be very helpful to make a diagnosis. This genetic testing process involves the analysis of the entire mitochondrial genome which encodes 13 proteins, 22 tRNAs and 2 ribosomal RNAs.
- Genes (37): MT-ATP6, MT-ATP8, MT-CO1, MT-CO2, MT-CO3, MT-CYB, MT-ND1, MT-ND2, MT-ND3, MT-ND4, MT-ND4L, MT-ND5, MT-ND6, MT-TA, MT-TC, MT-TD, MT-TE, MT-TF, MT-TG, MT-TH, MT-TI, MT-TK, MT-TL1, MT-TL2, MT-TM, MT-TN, MT-TP, MT-TQ, MT-TR, MT-TS1, MT-TS2, MT-TT, MT-TV, MT-TW, MT-TY, MT-RNR1, and MT-RNR2
Test Code: 8100
• Patient with clinical symptoms or pathology study suspected of a mitochondrial disorder
• Molecular confirmation of a clinical diagnosis
Test Info Sheet: Comprehensive Mitochondrial Genome Analysis
- Requisition: Mitochondrial Test Requisition Form
- Turn-Around Time: 2-4 Weeks
- Preferred Specimen: 3-5 mL Whole Blood – Lavender Top Tube
- Other Specimens: See details here
- CPT Codes: 81460, 81465
Pricing: Please contact us at (949) 916-8886 or firstname.lastname@example.org
- Methodology: Long-range PCR followed by Next-Generation Sequencing (NGS)
- Related Tests:
Mitochondrial DNA Deletion Analysis
Mitochondrial Nuclear Gene Panel
Mitochondrial Depletion Syndrome Panel
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