Activity

Filter

Cancel
Date Panel Item Activity
9 actions
Mendeliome v1.343 CBS Zornitza Stark Tag treatable tag was added to gene: CBS.
Mendeliome v0.8335 IMPDH2 Laura Raiti gene: IMPDH2 was added
gene: IMPDH2 was added to Mendeliome. Sources: Literature
Mode of inheritance for gene: IMPDH2 was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Publications for gene: IMPDH2 were set to PMID: 33098801
Phenotypes for gene: IMPDH2 were set to Dystonia
Review for gene: IMPDH2 was set to GREEN
Added comment: 6 unrelated individuals
1x individual in a dystonia cohort index case with infancy-onset dystonia and other neurological manifestations with a de-novo missense variant, c.338G>A (p.Gly113Glu) in IMPDH2, predicted to disrupt an invariant residue within the cystathionine-β-synthase (CBS) domain pair of the encoded protein.
IMPDH2 encodes IMPDH2, a key enzyme in the purine biosynthetic pathway, expressed throughout the brain and not linked previously to any human Mendelian condition.
1x individual with a de-novo substitution, c.337G>A (p.Gly113Arg), was found in in-house whole-exome sequencing data from 500 individuals with neurodevelopmental disorders. Through GeneMatcher, de novo variants identified:
3 x missense: c.729G>C (p.Gln243His), c.619G>C (p.Gly207Arg), and c.619G>A (p.Gly207Arg)
1 x deletion: c.478_480delTCC (p.Ser160del)
The six variants were predicted to be deleterious and none of them seen in control databases. All affected conserved amino acids and resided in and around the cystathionine-β-synthase domain pair.
The described variants are situated in and around the CBS domain pair, a regulatory element in which clustering of pathogenic missense variants has already been shown for the homologue of IMPDH2, IMPDH1.

The variant carriers shared similar neurodevelopmental phenotypes. Apart from the dystonia cohort index case, one participant had evidence of dystonic posturing. Modelling of the variants on 3D protein structures revealed spatial clustering near specific functional sites, predicted to result in deregulation of IMPDH2 activity. Additionally, thermal-shift assays showed that the c.619G>A (p.Gly207Arg) variant, identified as within the CBS domain pair, and c.729G>C (p.Gln243His), which is in close vicinity, affected the stability or folding behaviour of IMPDH2.
Sources: Literature
Mendeliome v0.1830 CBS Zornitza Stark Marked gene: CBS as ready
Mendeliome v0.1830 CBS Zornitza Stark Gene: cbs has been classified as Green List (High Evidence).
Mendeliome v0.1830 CBS Zornitza Stark Phenotypes for gene: CBS were changed from to Homocystinuria, B6-responsive and nonresponsive types, 236200; Thrombosis, hyperhomocysteinemic, 236200
Mendeliome v0.1829 CBS Zornitza Stark Publications for gene: CBS were set to
Mendeliome v0.1828 CBS Zornitza Stark Mode of inheritance for gene: CBS was changed from Unknown to BIALLELIC, autosomal or pseudoautosomal
Mendeliome v0.1827 CBS Kristin Rigbye reviewed gene: CBS: Rating: GREEN; Mode of pathogenicity: None; Publications: 7506602, 10338090; Phenotypes: Homocystinuria, B6-responsive and nonresponsive types, 236200, Thrombosis, hyperhomocysteinemic, 236200; Mode of inheritance: BIALLELIC, autosomal or pseudoautosomal
Mendeliome v0.0 CBS Zornitza Stark gene: CBS was added
gene: CBS was added to Mendeliome_VCGS. Sources: Expert Review Green,Victorian Clinical Genetics Services
Mode of inheritance for gene: CBS was set to Unknown