Intellectual disability - microarray and sequencing
Gene: CSNK1G1 Green List (high evidence)The rating of this gene has been updated following NHS Genomic Medicine Service approval.Created: 9 Mar 2022, 3:40 p.m. | Last Modified: 9 Mar 2022, 3:40 p.m.
Panel Version: 3.1510
Comment on list classification: Upgraded from Red to Amber as now at least 5 unrelated individuals reported (PMID: 33009664). All present developmental delay of varying severity, although a formal ID assessment was not performed. Tagged 'for-review' to evaluate relevance of the phenotypes to this panel.Created: 21 Dec 2020, 2:10 p.m. | Last Modified: 21 Dec 2020, 2:10 p.m.
Panel Version: 3.666
I don't know
Gold et al (2020 - PMID: 33009664) report 5 individuals with CSNK1G1 variants, including updated information on a previously reported subject (Martin et al 2014 - PMID: 24463883).
Features included DD (5/5) with associated expressive language delay, ASD (in at least 3/5), seizures (2/5), dysmorphic facial features (4/5 arched eyebrows, 3/5 prominent central incisors, 2/5 epicanthus) and limb anomalies (2/5 - proximally placed thumb, 5th f. clinodactyly, asymmetric overgrowth - the other individual had tapering fingers). GI problems were observed in 4/5. Two individuals had macrocephaly and one had microcephaly. There was no formal developmental assessment although ID might be implied in at least 3 individuals (p1: 20y - single words/regression in walking following a seizure episode, p2: 8y - first words at 5y, assistance to feed, dress and bathe, ASD, p4: 13y - regression, assistance to feed and dress).
CSNK1G1 encodes the gamma-1 isoform of casein kinase 1, a protein involved in growth and cell morphogenesis. The gene has ubiquitous expression, incl. brain. As commented, in brain it regulates phosphorylation of NMDA receptors, playing a role in synaptic transmission (4 articles cited).
One individual had a 1.2 kb deletion spanning exon 3 of CSNK1G1 [chr15:64550952-64552120 - GRCh37]. Parental samples were unavailable for this individual. Four individuals were found to harbor de novo CSNK1G1 variants [NM_022048.3: c.688C>T - p.(Arg230Trp) dn | c.1255C>T - p.(Gln419*) dn | c.1214+5G>A dn with in silico predictions in favor of splice disruption | c.419C>T - p.(Thr140Met) dn].
Arg230Trp is however present once in gnomAD. The stopgain variant is located in the last exon and predicted to skip NMD.
There were no variant studies performed.
The Drosophila gish gene encodes a CK1γ homolog with preferential expression in the mushroom body. Heterozygous and homozygous mutants exhibit impairment in memory retention, more severe in homozygous flies. gish was also identified as a seizure modifier in a fly epilepsy model (heterozygous para mt flies).
The authors also speculate that impaired transduction of LRP6 (and WNT signaling) might be implicated.
Finally the authors discuss the phenotype of individuals in Decipher one of whom (327861) harbors a frameshift variant and presenting ID, epilepsy and progressive spasticity. [NB. Inheritance of this variant is not specified, while this individual has a further inherited SCN2A missense SNV]. Two further Decipher cases with microdeletions spanning CSNK1G1 (and additional variants) are also discussed.
Overall, this gene can be considered for inclusion with probably amber rating.Created: 17 Oct 2020, 11:41 p.m. | Last Modified: 17 Oct 2020, 11:41 p.m.
Panel Version: 3.456
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
Phenotypes
Global developmental delay; Intellectual disability; Autism; Seizures; Abnormality of the face; Abnormality of limbs
Publications
Red List (low evidence)
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
EARLY INFANTILE EPILEPTIC ENCEPHALOPATHY AND MICROCEPHALY
Publications
Red List (low evidence)
One patient reported with severe non-syndromic early-onset epilepsy.Created: 27 Oct 2017, 2:46 p.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
Phenotypes
severe non-syndromic early-onset epilepsy
Publications
Red List (low evidence)
Tag gene-checked tag was added to gene: CSNK1G1.
Tag for-review was removed from gene: CSNK1G1.
Source Expert Review Green was added to CSNK1G1. Rating Changed from Amber List (moderate evidence) to Green List (high evidence)
Gene: csnk1g1 has been classified as Amber List (Moderate Evidence).
Tag for-review tag was added to gene: CSNK1G1.
Phenotypes for gene: CSNK1G1 were changed from severe non-syndromic early-onset epilepsy to severe non-syndromic early-onset epilepsy; Global developmental delay; Intellectual disability; Autism; Seizures; Abnormality of the face; Abnormality of limbs
Publications for gene: CSNK1G1 were set to 24463883
12.03.2018: Due to major updates completed (Phase 1, 2 and 3), this panel was promoted to Version 2 in order to reflect the major updates since November 2017 which have resulted in reviews for 836 genes added by Genomics England Curators and the Clinical Team, 130 new Green genes added to the interpretation pipeline (from 751 to 881 Green genes), and the gene total has increased from 1879 to 1927.
Model of inheritance for gene CSNK1G1 was set to MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
The Gel status was updated for this whole panel
The Gel status was updated for this whole panel
CSNK1G1 was added to Intellectual disabilitypanel. Sources: Expert Review Red
CSNK1G1 was created by ellenmcdonagh
If promoting or demoting a gene, please provide comments to justify a decision to move it.
Genes included in a Genomics England gene panel for a rare disease category (green list) should fit the criteria A-E outlined below.
These guidelines were developed as a combination of the ClinGen DEFINITIVE evidence for a causal role of the gene in the disease(a), and the Developmental Disorder Genotype-Phenotype (DDG2P) CONFIRMED DD Gene evidence level(b) (please see the original references provided below for full details). These help provide a guideline for expert reviewers when assessing whether a gene should be on the green or the red list of a panel.
A. There are plausible disease-causing mutations(i) within, affecting or encompassing an interpretable functional region(ii) of this gene identified in multiple (>3) unrelated cases/families with the phenotype(iii).
OR
B. There are plausible disease-causing mutations(i) within, affecting or encompassing cis-regulatory elements convincingly affecting the expression of a single gene identified in multiple (>3) unrelated cases/families with the phenotype(iii).
OR
C. As definitions A or B but in 2 or 3 unrelated cases/families with the phenotype, with the addition of convincing bioinformatic or functional evidence of causation e.g. known inborn error of metabolism with mutation in orthologous gene which is known to have the relevant deficient enzymatic activity in other species; existence of an animal model which recapitulates the human phenotype.
AND
D. Evidence indicates that disease-causing mutations follow a Mendelian pattern of causation appropriate for reporting in a diagnostic setting(iv).
AND
E. No convincing evidence exists or has emerged that contradicts the role of the gene in the specified phenotype.
(i)Plausible disease-causing mutations: Recurrent de novo mutations convincingly affecting gene function. Rare, fully-penetrant mutations - relevant genotype never, or very rarely, seen in controls. (ii) Interpretable functional region: ORF in protein coding genes miRNA stem or loop. (iii) Phenotype: the rare disease category, as described in the eligibility statement. (iv) Intermediate penetrance genes should not be included.
It’s assumed that loss-of-function variants in this gene can cause the disease/phenotype unless an exception to this rule is known. We would like to collect information regarding exceptions. An example exception is the PCSK9 gene, where loss-of-function variants are not relevant for a hypercholesterolemia phenotype as they are associated with increased LDL-cholesterol uptake via LDLR (PMID: 25911073).
If a curated set of known-pathogenic variants is available for this gene-phenotype, please contact us at [email protected]
We classify loss-of-function variants as those with the following Sequence Ontology (SO) terms:
Term descriptions can be found on the PanelApp homepage and Ensembl.
If you are submitting this evaluation on behalf of a clinical laboratory please indicate whether you report variants in this gene as part of your current diagnostic practice by checking the box
Standardised terms were used to represent the gene-disease mode of inheritance, and were mapped to commonly used terms from the different sources. Below each of the terms is described, along with the equivalent commonly-used terms.
A variant on one allele of this gene can cause the disease, and imprinting has not been implicated.
A variant on the paternally-inherited allele of this gene can cause the disease, if the alternate allele is imprinted (function muted).
A variant on the maternally-inherited allele of this gene can cause the disease, if the alternate allele is imprinted (function muted).
A variant on one allele of this gene can cause the disease. This is the default used for autosomal dominant mode of inheritance where no knowledge of the imprinting status of the gene required to cause the disease is known. Mapped to the following commonly used terms from different sources: autosomal dominant, dominant, AD, DOMINANT.
A variant on both alleles of this gene is required to cause the disease. Mapped to the following commonly used terms from different sources: autosomal recessive, recessive, AR, RECESSIVE.
The disease can be caused by a variant on one or both alleles of this gene. Mapped to the following commonly used terms from different sources: autosomal recessive or autosomal dominant, recessive or dominant, AR/AD, AD/AR, DOMINANT/RECESSIVE, RECESSIVE/DOMINANT.
A variant on one allele of this gene can cause the disease, however a variant on both alleles of this gene can result in a more severe form of the disease/phenotype.
A variant in this gene can cause the disease in males as they have one X-chromosome allele, whereas a variant on both X-chromosome alleles is required to cause the disease in females. Mapped to the following commonly used term from different sources: X-linked recessive.
A variant in this gene can cause the disease in males as they have one X-chromosome allele. A variant on one allele of this gene may also cause the disease in females, though the disease/phenotype may be less severe and may have a later-onset than is seen in males. X-linked inactivation and mosaicism in different tissues complicate whether a female presents with the disease, and can change over their lifetime. This term is the default setting used for X-linked genes, where it is not known definitately whether females require a variant on each allele of this gene in order to be affected. Mapped to the following commonly used terms from different sources: X-linked dominant, x-linked, X-LINKED, X-linked.
The gene is in the mitochondrial genome and variants within this can cause this disease, maternally inherited. Mapped to the following commonly used term from different sources: Mitochondrial.
Mapped to the following commonly used terms from different sources: Unknown, NA, information not provided.
For example, if the mode of inheritance is digenic, please indicate this in the comments and which other gene is involved.