Genomic newborn screening: BabyScreen+
Gene: GLA Green List (high evidence)Green List (high evidence)
Assessed as 'moderate actionability' in paediatric patients by ClinGen.
In classic FD, the first symptoms, including chronic neuropathic pain and episodic severe pain crises, emerge during childhood (typically age 3-10 years). Heterozygous females typically have a later median age of onset than males (9-13 years versus 13-23 years). Rarely, females may be relatively asymptomatic and have a normal life span or may have symptoms as severe as males with the classic phenotype.
Cardiac and/or cerebrovascular disease is present in most males by middle age while ESRD usually develops during the third to fifth decade. Renal and cardiac failure represent major sources of morbidity, and account for the reduced lifespan among affected males (50-58 years) and females (70-75 years) compared to the normal population.
A systematic review of RCTs of ERT reported on nine studies of 351 FD patients; however, many of these studies reported only on the effect of ERT on levels of enzyme substrate. Data from 2 trials (n=39 males) found no statistically significant differences in plasma enzyme substrate and one trial (n=24 males) found no statistical differences in renal function between individuals treated with agalsidase alfa and placebo (up to 6-month follow-up). Similar results were seen for agalsidase beta. One trial of 26 male patients found a statistically significant difference in pain, favoring agalsidase alfa compared to placebo at 5-6 months after treatment. No trial reported on the effect of agalsidase alfa on mortality or cardiac/cerebrovascular disease. One trial of agalsidase beta (n=82 males and females) found no difference in mortality, renal function, or symptoms or complications of cardiac or cerebrovascular disease over 18 months. The long-term influence of ERT on risk of morbidity and mortality related to FD remains to be established.
Migalastat, an oral chaperone drug, is recommended as an option for treatment for some patients with FD who are over 16 years with an amenable genetic variant who would usually be offered ERT. For non-amenable genotypes, migalastat may result in a net loss of alpha-Gal A activity, potentially worsening the disease condition.
A systematic review evaluated 2 phase III RCTs that both included males and females. One RCT randomized patients to switch from ERT to migalastat (n = 36) or continue with ERT (n = 24) during an 18-month period with a 12-month extension in which all patients received migalastat. During the treatment period, the percentage of patients who had a renal, cardiac, or cerebrovascular event or died was 29% of patients on migalastat compared to 44% of patients on ERT. However, this difference was not statistically significant. A second RCT compared migalastat (n=34) with placebo (n=33) over a 6-month period, with an 18-month extension study. The primary outcome was change from baseline in interstitial capillary inclusions of the enzyme substrate globotriaosylceramide (GL-3), which was not significantly different between groups. Results from both trials indicate that migalastat does not have a significant beneficial effect on pain, health-related quality of life outcomes, or glomerular filtration rate (results were uncertain due to large confidence intervals, small sample sizes, and/or short follow-up time). Migalastat did not influence left ventricular ejection fraction but did improve left ventricular mass over 18 months.
There are a number of recommendations for surveillance and agents to avoid (amiodarone). There is no consensus as to when ERT should be started. Note ERT is licensed in Australia from age 7 years.
However, carbamazepine relieves neuropathic pain, which has onset in early childhood. Overall, include.Created: 11 Dec 2022, 10:35 p.m. | Last Modified: 17 Jan 2023, 7:17 a.m.
Panel Version: 0.1834
Mode of inheritance
X-LINKED: hemizygous mutation in males, biallelic mutations in females
Phenotypes
Fabry disease (MIM# 301500)
Green List (high evidence)
age of onset in males for the classic form of the disorder is 4 - 8 years of age
see: https://www.ncbi.nlm.nih.gov/books/NBK1292/
Treatments:
carbamazepine for the neuropathic pain
enzyme replacement therapy availableCreated: 20 Nov 2022, 6 a.m. | Last Modified: 20 Nov 2022, 6 a.m.
Panel Version: 0.950
Mode of inheritance
X-LINKED: hemizygous mutation in males, monoallelic mutations in females may cause disease (may be less severe, later onset than males)
Phenotypes
neuropathic pain; cardiomyopathy; cataract; agniokeratomata; deafness; hypohidrosis; stroke; renal failure
Publications
Tag for review was removed from gene: GLA.
Tag for review tag was added to gene: GLA.
Gene: gla has been classified as Green List (High Evidence).
Phenotypes for gene: GLA were changed from Fabry disease to Fabry disease (MIM# 301500)
Publications for gene: GLA were set to
Tag treatable tag was added to gene: GLA. Tag metabolic tag was added to gene: GLA.
gene: GLA was added gene: GLA was added to gNBS. Sources: BabySeq Category A gene,Expert Review Green Mode of inheritance for gene: GLA was set to X-LINKED: hemizygous mutation in males, biallelic mutations in females Phenotypes for gene: GLA were set to Fabry disease
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 panelapp@genomicsengland.co.uk
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.