GTF3C1

Chr 16

general transcription factor IIIC subunit 1

Also known as: TFIIIC, TFIIIC220, TFIIICalpha

NCBI Gene: 2975 ENSG00000077235 UniProt: Q12789 OMIM: 603246

Encodes a component of transcription factor TFIIIC that is required for RNA polymerase III-mediated transcription of tRNA, 5S rRNA, and other stable RNAs. Mutations cause autosomal recessive neurodevelopmental disorders with intellectual disability and seizures. This gene is highly constrained against loss-of-function mutations (pLI ~1.0), indicating that haploinsufficiency is likely incompatible with normal development.

OMIM ResearchSummary from RefSeq, UniProt

Enables RNA polymerase III general transcription initiation factor activity. Involved in transcription initiation at RNA polymerase III promoter. Located in nucleoplasm. Part of transcription factor TFIIIC complex. [provided by Alliance of Genome Resources, Jun 2026]

OMIM 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.

Active trials

Pubs (1 yr)

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P/LP submissions

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P/LP missense

0.17

LOEUF· LoF intol.

LOF

Mechanism· predicted