Microcephaly
Gene: RAC1

RAC1 (Rac family small GTPase 1)
EnsemblGeneIds (GRCh38): ENSG00000136238
EnsemblGeneIds (GRCh37): ENSG00000136238
OMIM: 602048, Gene2Phenotype
RAC1 is in 6 panels

1 review

Zornitza Stark (Victorian Clinical Genetics Services; Australian Genomics)

Green List (high evidence)

Additional patients reported. Microcephaly is a feature, though variable one, and some individuals have macrocephaly.
Created: 5 Jan 2023, 3:18 a.m. | Last Modified: 5 Jan 2023, 3:18 a.m.

Panel Version: 1.180

At least 7 individuals reported so far, all variants missense, most de novo. Hotspot/cluster in GTP binding motif.1 paper postulated toxic GoF as the mechanism of disease (PMID: 30293988), however another suggested LoF, and functional studies have yet to be performed in patient cells (PMID: 30042656). Phenotypic variability may be related to mutational mechanism.
Microcephaly is not a consistent feature: Four patients had microcephaly (-2.5 to -5 SD), 1 was normocephalic, and 2 had macrocephaly (+4.16 and +4.5 SD). Given the small number of individuals reported, remains to be seen how common microcephaly is in this condition, and whether it can be linked to particular mutational spectrum.
Created: 6 Aug 2020, 8 a.m. | Last Modified: 6 Aug 2020, 8 a.m.

Panel Version: 0.143

Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted

Phenotypes
Mental retardation, autosomal dominant 48, MIM# 617751

Publications

Created: 6 Aug 2020, 8 a.m.
Last Modified: 6 Aug 2020, 8 a.m.
Panel version: 1.180

Details

Mode of Inheritance

MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted

Sources

Expert Review Green
Victorian Clinical Genetics Services

Phenotypes

Mental retardation, autosomal dominant 48, MIM# 617751

OMIM

602048

Clinvar variants

Variants in RAC1

Penetrance

None

Publications

Panels with this gene