rs759875552
Variant summary
Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PS1_ModeratePM2PM5PP2PP3
The NM_024301.5(FKRP):c.586G>A(p.Gly196Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000019 in 1,579,308 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G196V) has been classified as Likely pathogenic.
Frequency
Consequence
NM_024301.5 missense
Scores
Clinical Significance
Conservation
Publications
- autosomal recessive limb-girdle muscular dystrophy type 2IInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics
- muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A5Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, G2P, Ambry Genetics
- muscular dystrophy-dystroglycanopathy type B5Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Myriad Women’s Health, Labcorp Genetics (formerly Invitae)
- myopathy caused by variation in FKRPInheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
- congenital muscular dystrophy with cerebellar involvementInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- congenital muscular dystrophy with intellectual disabilityInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- congenital muscular dystrophy without intellectual disabilityInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- muscle-eye-brain diseaseInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- muscular dystrophy-dystroglycanopathy, type AInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
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ACMG classification
Our verdict: Likely_pathogenic. The variant received 8 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| FKRP | NM_024301.5 | c.586G>A | p.Gly196Arg | missense_variant | Exon 4 of 4 | ENST00000318584.10 | NP_077277.1 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000132 AC: 2AN: 151832Hom.: 0 Cov.: 33 show subpopulations
GnomAD4 exome AF: 7.01e-7 AC: 1AN: 1427476Hom.: 0 Cov.: 32 AF XY: 0.00000141 AC XY: 1AN XY: 709484 show subpopulations
GnomAD4 genome AF: 0.0000132 AC: 2AN: 151832Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1AN XY: 74172 show subpopulations
ClinVar
Submissions by phenotype
Walker-Warburg congenital muscular dystrophy Pathogenic:1
ClinVar contains an entry for this variant (Variation ID: 197342). This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 196 of the FKRP protein (p.Gly196Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of limb girdle muscular dystrophy (PMID: 18832576, 24257234, 32429923; Invtiae, external communication). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on FKRP protein function. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -
not specified Uncertain:1
Variant summary: FKRP c.586G>A (p.Gly196Arg) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 193272 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.586G>A in individuals affected with Limb-Girdle Muscular Dystrophy, Autosomal Recessive and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 197342). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Autosomal recessive limb-girdle muscular dystrophy type 2I Uncertain:1
This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -
Autosomal recessive limb-girdle muscular dystrophy type 2I;C1847759:Muscular dystrophy-dystroglycanopathy type B5;C3150413:Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A5;C4284790:Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A1 Uncertain:1
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not provided Uncertain:1
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Cardiovascular phenotype Uncertain:1
The p.G196R variant (also known as c.586G>A), located in coding exon 1 of the FKRP gene, results from a G to A substitution at nucleotide position 586. The glycine at codon 196 is replaced by arginine, an amino acid with dissimilar properties. This variant has co-occurred with other variants in FKRP in individuals with features of limb girdle muscular dystrophy; however, details were limited (Kesari A et al. Am J Pathol, 2008 Nov;173:1476-87; Murphy LB et al. Ann Clin Transl Neurol, 2020 May;7:757-766; Leung DG et al. BMC Neurol, 2020 May;20:196). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this alteration remains unclear. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at