protein
T-box brain protein 1
aka T-brain-1, TBR-1
Gene
TBR1
Organism
Homo sapiens(9606)
Length
682 aa
Mass
74,053 Da
TBR1 (T-box brain protein 1) is a transcriptional repressor that plays critical roles in cortical development. It regulates multiple developmental processes including neuronal migration, laminar and areal identity specification, and axonal projection patterning. TBR1 functions as a repressor of FEZF2, thereby controlling the formation of corticospinal tracts by restricting their origin to layer 5 neurons rather than layer 6 projection neurons (UniProt: Q16650).
TBR1 is expressed during cortical development and is associated with intellectual developmental disorder with autism and speech delay (IDDAS), an autosomal dominant neurodevelopmental condition characterized by intellectual disability, autism spectrum disorder features, and language deficits. Mutations in TBR1 disrupt normal cortical circuit formation and neuronal organization.
TBR1 is classified as a SFARI Category 1 gene, indicating strong evidence for association with autism spectrum disorder (SFARI Cat 1). Its role in cortical patterning and neuronal connectivity makes it central to understanding the neurodevelopmental basis of autism and related cognitive and language impairments.
Generated from the curated entity record below. May contain errors — verify against source links.
Genetic Evidence · ASD
High confidence — strong genetic evidence from multiple studies
Source: SFARI Gene database · gene.sfari.org
Related Publications
Browse all →Inherited and De Novo Genetic Risk for Autism Impacts Shared Networks.
Ruzzo Elizabeth K et al.Cell2019PMID 31398340Inherited and multiple de novo mutations in autism/developmental delay risk genes suggest a multifactorial model.
Guo Hui et al.Molecular autism2018PMID 30564305Whole genome sequencing resource identifies 18 new candidate genes for autism spectrum disorder.
C Yuen Ryan K et al.Nature neuroscience2017PMID 28263302Identification of common genetic risk variants for autism spectrum disorder.
Grove Jakob et al.Nature genetics2019PMID 30804558Synaptic, transcriptional and chromatin genes disrupted in autism.
De Rubeis Silvia et al.Nature2014PMID 25363760
Function
Transcriptional repressor involved in multiple aspects of cortical development, including neuronal migration, laminar and areal identity, and axonal projection (PubMed:25232744, PubMed:30250039). As transcriptional repressor of FEZF2, it blocks the formation of the corticospinal (CS) tract from layer 6 projection neurons, thereby restricting the origin of CS axons specifically to layer 5 neurons (By similarity)
Disease associations
Intellectual developmental disorder with autism and speech delayIDDAS
An autosomal dominant neurodevelopmental disorder characterized by varying degrees of intellectual disability, autism spectrum disorder, and language deficits.
Sources
Last updated 5/6/2026, 5:25:13 AM