TOMM20 (translocase of outer mitochondrial membrane 20 homolog)
TOMM20 Sequencing
MITOCHONDRIAL DNA ANALYSIS
Also known as: TOM20

Description:

Mitochondrial biogenesis requires the import of approximately up to 1000 proteins into mitochondria. The protein import pathway relies on hetero-oligomeric translocase complexes in both inner (TIMM) and outer (TOMM) mitochondrial membranes. The translocase in the outer membrane, the TOM complex, is composed of a core complex formed from the β-barrel channel Tom40 and additional subunits each with single, α-helical transmembrane segments. The master receptor subunit of the TOM complex, TOMM20, recognizes the targeting sequence on incoming mitochondrial precursor proteins, binds to these protein ligands, and then transfers them to the core complex for translocation across the outer membrane. Mutations in the transmembrane segment that destabilize TOMM20, prevent TOMM20 from functioning as a receptor for protein import into mitochondria. Mutant yeast cells that included a defective gene for TOMM20 homolog (MOM19) showed dramatically decrease in most of the respiratory chain enzyme activity. TOMM20 gene maps to chromosome 1q42.3. It contains 5 coding exons, and encodes for a protein of 145 amino acids.

Reasons for Referral:

  • Confirmation of a clinical diagnosis
  • Carrier testing

Testing Methodology:

The exons and flanking intronic regions of the TOMM20 gene are PCR amplified and sequenced in both the forward and reverse directions.

Specimen Requirements:

Blood: EDTA (purple-top) tubes: Adult: 14 cc; Child: 6 cc; Infant: 3 cc
Requisition form must accompany the specimen. To receive forms, additional information or specimen collection kits, please contact the laboratory.

Turnaround Time:

Index: 4 weeks
KFM: 2 weeks

CPT Codes and Prices:

Index: 83891, 83904x10, 83898x5, 83912, 83894x2
Known Familial Mutation: 83904x4, 83898x2, 83912, 83891, 83894x2

Shipping Information

Forms:

>> Gene Sequencing Requisition or Mitochondrial Requisition - Mitochondrial Diagnostic Checklist is included

Test Code:

Index: 3475
Known Familial Mutation: 3476