CCNT1

Chr 12

cyclin T1

Also known as: CCNT, CYCT1, HIVE1

NCBI Gene: 904ENSG00000129315UniProt: O60563

This gene encodes a member of the highly conserved cyclin C subfamily. The encoded protein tightly associates with cyclin-dependent kinase 9, and is a major subunit of positive transcription elongation factor b (p-TEFb). In humans, there are multiple forms of positive transcription elongation factor b, which may include one of several different cyclins along with cyclin-dependent kinase 9. The complex containing the encoded cyclin and cyclin-dependent kinase 9 acts as a cofactor of human immunodeficiency virus type 1 (HIV-1) Tat protein, and is both necessary and sufficient for full activation of viral transcription. This cyclin and its kinase partner are also involved in triggering transcript elongation through phosphorylation of the carboxy-terminal domain of the largest RNA polymerase II subunit. Overexpression of this gene is implicated in tumor growth. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Apr 2013]

ResearchGenerating clinical summary…

Clinical highlights

Interpreting a novel variant
This gene is strongly intolerant of loss-of-function variation in the population, so LoF variants warrant close attention. No curated mechanism annotation is available — see the mechanism card for the computational prediction and its caveats.Based on population constraint only.
0
Active trials
4
Pubs (1 yr)
—
P/LP submissions
—
P/LP missense
0.50
LOEUF
—
Mechanism
Some data sources returned errors (1)

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
Moderate LoF intolerance
LoF Constraint?
0.50LOEUF
pLI 0.051
Z-score 3.62
OE 0.28 (0.16–0.50)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint?
1.08Z-score
OE missense 0.85 (0.77–0.93)
333 obs / 393.1 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.28 (0.16–0.50)
0≤0.351.4
Missense OE?0.85 (0.77–0.93)
0≤0.61.4
Synonymous OE?1.03
0≤1.21.6
LoF obs/exp: 8 / 29.0Missense obs/exp: 333 / 393.1Syn Z: -0.28

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

CCNT1 · protein map & ClinVar variants

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

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →

External Resources

Links to major genomics databases and tools

Franklin by Genoox
AI-powered variant curation and clinical analysis
DECIPHER
Genomic variants and phenotypes in rare disease patients