MT-CYB

Chr MT

cytochrome b

Also known as: MTCYB

NCBI Gene: 4519ENSG00000198727UniProt: P00156

Predicted to enable metal ion binding activity. Predicted to contribute to ubiquinol-cytochrome-c reductase activity. Predicted to be involved in mitochondrial electron transport, ubiquinol to cytochrome c. Located in mitochondrial inner membrane. Implicated in ovarian carcinoma and urinary bladder cancer. [provided by Alliance of Genome Resources, Apr 2025]

Primary Disease Associations & Inheritance

UniProtCardiomyopathy, infantile histiocytoid
UniProtLeber hereditary optic neuropathy
337
ClinVar variants
13
Pathogenic / LP
—
pLI score
2
Active trials
Clinical Summary— MT-CYB
🧬
Gene-Disease Validity (ClinGen)
mitochondrial disease · MTDefinitive

Definitive — sufficient evidence for diagnostic panels

📋
ClinVar Variants
13 Pathogenic / Likely Pathogenic· 139 VUS of 337 total submissions
💊
Clinical Trials
2 active or recruiting trials — potential therapeutic options may be available
Some data sources returned errors (1)

clinvar: Error: NCBI fetch failed: 429 https://eutils.ncbi.nlm.nih.gov/entrez/eutils/esummary.fcgi

Population Genetics & Constraint

gnomAD

Constraint data not available from gnomAD.

ClinVar Variant Classifications

337 submitted variants in ClinVar

ClinVar

Classification Summary

Pathogenic7
Likely Pathogenic6
VUS139
Likely Benign67
Benign117
Conflicting1
7
Pathogenic
6
Likely Pathogenic
139
VUS
67
Likely Benign
117
Benign
1
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories· variant type breakdown unavailable

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
————7
Likely Pathogenic
————6
VUS
————139
Likely Benign
————67
Benign
————117
Conflicting
—1
Total—337

Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

MT-CYB · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

OMIM — Genotype-Phenotype Relationships

1 OMIM entry

OMIM
📖
GeneReview available — MT-CYB
Authoritative clinical overview · NCBI Bookshelf · Recommended first read
Open GeneReview ↗
Clinical Literature
Landmark / reviewRecent case evidence
Key Publications
Landmark & review papers · by relevance
PubMed
Association between the single nucleotide variants of the mitochondrial cytochrome B gene (MT-CYB) and the male infertility.
Saleh Jaweesh M et al.·Mol Biol Rep
2022
Atypical Leber Hereditary Optic Neuropathy (LHON) Associated with a Novel MT-CYB:m.15309T>C(Ile188Thr) Variant.
Petrovic Pajic S et al.·Genes (Basel)
2025Case report
Evaluating the MT-CYB and MT-ATP6 variations in COVID-19 patients: A case-control study.
Sultana GNN et al.·PLoS One
2025Cohort
Single nucleotide polymorphism rs527236194 of the cytochrome B gene (MT-CYB) is associated with alterations in sperm parameters.
Gromenko YY et al.·Mol Biol Rep
2023
Adult Leigh Syndrome Associated with the m.15635T>C Mitochondrial DNA Variant Affecting the Cytochrome b (MT-CYB) Gene.
Tropeano CV et al.·Int J Mol Sci
2025Case report
Mitochondrial DNA variant spectrum and the association with chronic tic disorders.
Jiang P et al.·Eur J Neurol
2022
Loss of ELF2 drives topotecan resistance in retinoblastoma revealed by genome-wide CRISPR-Cas9 screening.
Jiang J et al.·Cell Death Dis
2025
Prognostic landscape of mitochondrial genome in myelodysplastic syndrome after stem-cell transplantation.
Dong J et al.·J Hematol Oncol
2023
Somatic Mitochondrial Mutations in Oral Cavity Cancers among Senegalese Patients.
Toure S et al.·Asian Pac J Cancer Prev
2019Cohort
A novel in-frame 18-bp microdeletion in MT-CYB causes a multisystem disorder with prominent exercise intolerance.
Carossa V et al.·Hum Mutat
2014Case report
Top 10 resultsSearch PubMed ↗
Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC
Top 5 resultsSearch Europe PMC ↗

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov
P47-Phox, Deficiency of

Lentiviral Gene Therapy for p47 AR-CGD

RECRUITING
NCT05207657Phase PHASE1, PHASE2Great Ormond Street Hospital for Children NHS Foundation TrustStarted 2023-03-20
Lentiviral vector transduced CD34+ cells
p47Autosomal RecessiveChronic Granulomatous Disease

pCCLCHIM-p47 (Lentiviral Vector Transduced CD34 Plus Cells) in Patients With p47 Autosomal Recessive Chronic Granulomatous Disease (AR-CGD)

ENROLLING BY INVITATION
NCT06253507Phase PHASE1, PHASE2National Institute of Allergy and Infectious Diseases (NIAID)Started 2024-06-25
Cryopreserved Autologous CD34+ cells transduced with pCCLCHIM-p47

External Resources

Links to major genomics databases and tools