Intellectual disability - microarray and sequencing
Gene: RASA1 Red List (low evidence)Following discussion with the clinical team, this gene has been demoted from Amber to Red, in accordance with the external review by Zornitza Stark and Konstantinos VarvagiannisCreated: 17 Aug 2020, 10:09 a.m. | Last Modified: 22 Sep 2020, 3:42 p.m.
Panel Version: 3.331
Red List (low evidence)
Intellect is typically normal.Created: 27 Feb 2020, 7:28 a.m. | Last Modified: 27 Feb 2020, 7:28 a.m.
Panel Version: 3.3
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Capillary malformation-arteriovenous malformation 1, MIM# 608354
Red List (low evidence)
I could not find any evidence of DD/ID being a feature of RASA1-related disorders.
Wooderchak-Donahue et al. (PMID: 29891884) report on 60 individuals with pathogenic variant in RASA1 (and 9 further with VUS). DD/ID was not reported in any of the patients.
Bayrak-Todemir and Stevenson (PMID: 21348050 - shared authors with the previous article) do a further review where they specify that DD and severe neurologic findings are observed only in contiguous 5q14.3 deletions encompassing both RASA1 and MEF2C and that these findings are not thought to be related to RASA1 deletion (note MEF2C is a confirmed DD gene). The authors cite an article by Carr et al. [PMID: 21626678].
The contribution of each gene in 5q14.3q15 deletions is also discussed in a further article by Zweier and Rauch (https://doi.org/10.1159/000337496).
RASA1 is a confirmed DD gene in G2P associated however with the aforementioned phenotypes (Capillary malformation-arteriovenous malformation and Parkes Weber syndrome).
The gene is not included in gene panels for intellectual disability offered by diagnostic laboratories.
As a result, this gene could possibly be demoted to red.Created: 15 Dec 2018, 7:32 a.m.
Publications
Green List (high evidence)
This is a pertinent gene from the NIHR BioResource - Rare Diseases Study (NIHRBR-RD) BRIDGE Study : SPEED (Specialist Pathology: Evaluating Exomes in Diagnostics) which covers epilepsies, movement and microcephaly disorders, this gene is on the SPEED_NEURO_20170705 gene list. Evidences used for SPEED NEURO gene list: in_ddg2p_20141118_conf;in_ddg2p_20141118_conf;in_ddg2p_201507;in_ddg2p_201507_conf;in_ddg2p_2_4_2017;in_ddg2p_2_4_2017_conf . Main mutation mechanism : Loss of functionCreated: 27 Jul 2017, 8:13 p.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown
Publications
Comment on list classification: This gene is from an expert list and needs further assessment by the Genomics England curation team to access inclusion and pertinence to this panel.Created: 28 Jul 2017, 3:28 p.m.
Gene: rasa1 has been classified as Red List (Low Evidence).
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.
This gene has been classified as Amber List (Moderate Evidence).
RASA1 was created by BRIDGE
RASA1 was added to Intellectual disabilitypanel. Sources: BRIDGE study SPEED NEURO Tier1 Gene
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.