protein
Son of sevenless homolog 1
aka SOS-1
Gene
SOS1
Organism
Homo sapiens(9606)
Length
1333 aa
Mass
152,464 Da
# SOS1 (Son of Sevenless Homolog 1)
SOS1 is a guanine nucleotide exchange factor that promotes the exchange of GDP for GTP on the Ras protein, thereby activating Ras signaling (UniProt: Q07889). It regulates phosphorylation of the mitogen-activated protein kinase MAPK3/ERK1 in response to epidermal growth factor stimulation and likely participates in signal transduction from Ras to Rac through its GEF activity.
SOS1 is implicated in two distinct genetic diseases. Mutations cause Noonan syndrome 4 (NS4), characterized by short stature, facial dysmorphia including hypertelorism and downward eyeslant, congenital heart defects, motor delay, variable intellectual deficits, and skeletal abnormalities. SOS1 is also associated with gingival fibromatosis 1 (GINGF1), a rare hereditary condition marked by progressive overgrowth of gingival tissue.
SOS1 is classified in the SFARI database as syndromic autism-associated (Category S) (SFARI Cat S), indicating a potential link to autism within the context of syndromic presentations, particularly Noonan syndrome, which can include neurodevelopmental features.
Generated from the curated entity record below. May contain errors — verify against source links.
Genetic Evidence · ASD
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
Promotes the exchange of Ras-bound GDP by GTP (PubMed:8493579). Probably by promoting Ras activation, regulates phosphorylation of MAP kinase MAPK3/ERK1 in response to EGF (PubMed:17339331). Catalytic component of a trimeric complex that participates in transduction of signals from Ras to Rac by promoting the Rac-specific guanine nucleotide exchange factor (GEF) activity (By similarity)
Disease associations
Fibromatosis, gingival, 1GINGF1
A form of hereditary gingival fibromatosis, a rare condition characterized by a slow, progressive overgrowth of the gingiva. The excess gingival tissue can cover part of or the entire crown, and can result in diastemas, teeth displacement, or retention of primary or impacted teeth. GINGF1 is usually transmitted as an autosomal dominant trait, although sporadic cases are common.
Noonan syndrome 4NS4
A form of Noonan syndrome, a disease characterized by short stature, facial dysmorphic features such as hypertelorism, a downward eyeslant and low-set posteriorly rotated ears, and a high incidence of congenital heart defects and hypertrophic cardiomyopathy. Other features can include a short neck with webbing or redundancy of skin, deafness, motor delay, variable intellectual deficits, multiple skeletal defects, cryptorchidism, and bleeding diathesis. Individuals with Noonan syndrome are at risk of juvenile myelomonocytic leukemia, a myeloproliferative disorder characterized by excessive production of myelomonocytic cells. Some patients with NS4 have polyarticular villonodular synovitis.
Sources
Last updated 5/6/2026, 5:24:45 AM