rs886042506

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_024301.5(FKRP):​c.162_165dup​(p.Phe56GlyfsTer6) variant causes a frameshift change. The variant allele was found at a frequency of 0.0000237 in 1,604,934 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

FKRP
NM_024301.5 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:7

Conservation

PhyloP100: 6.25
Variant links:
Genes affected
FKRP (HGNC:17997): (fukutin related protein) This gene encodes a protein which is targeted to the medial Golgi apparatus and is necessary for posttranslational modification of dystroglycan. Mutations in this gene have been associated with congenital muscular dystrophy, cognitive disability, and cerebellar cysts. Several alternatively spliced transcript variants of this gene have been described, but the full-length nature of some of these variants has not been determined. [provided by RefSeq, Oct 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 176 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 19-46755610-C-CGGGA is Pathogenic according to our data. Variant chr19-46755610-C-CGGGA is described in ClinVar as [Pathogenic]. Clinvar id is 282866.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
FKRPNM_024301.5 linkuse as main transcriptc.162_165dup p.Phe56GlyfsTer6 frameshift_variant 4/4 ENST00000318584.10 NP_077277.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
FKRPENST00000318584.10 linkuse as main transcriptc.162_165dup p.Phe56GlyfsTer6 frameshift_variant 4/41 NM_024301.5 ENSP00000326570 P1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152178
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000862
AC:
2
AN:
232120
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
126546
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000191
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000234
AC:
34
AN:
1452756
Hom.:
0
Cov.:
33
AF XY:
0.0000263
AC XY:
19
AN XY:
722400
show subpopulations
Gnomad4 AFR exome
AF:
0.0000300
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000279
Gnomad4 OTH exome
AF:
0.0000333
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152178
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74334
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000441
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000227

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingARUP Laboratories, Molecular Genetics and Genomics, ARUP LaboratoriesMar 24, 2022The FKRP c.162_165dup; p.Phe56GlyfsTer6 variant (rs886042506; also reported as 165InsGGAG; ClinVar Variation ID: 282866), has been previously identified in trans with other pathogenic variants in FKRP in at least two patients with symptoms of congenital muscular dystrophy and reduced glycosylated alpha-dystroglycan (Brockington 2001 and Peat 2008). This variant is only observed on two alleles in the Genome Aggregation Database, indicating it is not a common polymorphism. This variant results in a premature termination codon in the last (and only coding) exon of the FKRP gene. While this may not lead to nonsense-mediated decay, it is expected to create a truncated protein that would include a sequence of 6 amino acid residues not usually present. Additionally, several downstream truncating variants have been described in individuals with FKRP-related muscular dystrophy and are considered pathogenic (Selected references: Brockington 2001 and Matsumoto 2005). Based on the available information, the p.Phe56GlyfsTer6 variant is considered pathogenic. References: Brockington M et al. Mutations in the fukutin-related protein gene (FKRP) cause a form of congenital muscular dystrophy with secondary laminin alpha2 deficiency and abnormal glycosylation of alpha-dystroglycan. Am J Hum Genet. 2001 Dec;69(6):1198-209. PMID: 11592034 Matsumoto H et al. Congenital muscular dystrophy with glycosylation defects of alpha-dystroglycan in Japan. Neuromuscul Disord. 2005 May;15(5):342-8. PMID: 15833426. Peat RA et al. Diagnosis and etiology of congenital muscular dystrophy. Neurology. 2008 Jul 29;71(5):312-21. PMID: 18160674. -
Pathogenic, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Aug 25, 2015- -
Autosomal recessive limb-girdle muscular dystrophy type 2I Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingCounsylFeb 01, 2017- -
Autosomal recessive limb-girdle muscular dystrophy Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpAug 09, 2024Variant summary: FKRP c.162_165dupGGAG (p.Phe56GlyfsX6) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant allele was found at a frequency of 8.6e-06 in 232120 control chromosomes. c.162_165dupGGAG has been reported in the literature in individuals affected with Limb-Girdle Muscular Dystrophy, Autosomal Recessive. Additionally, variants downstream of this position have been classified as pathogenic by our lab. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. ClinVar contains an entry for this variant (Variation ID: 282866). Based on the evidence outlined above, the variant was classified as pathogenic. -
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 Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingCenter for Genomics, Ann and Robert H. Lurie Children's Hospital of ChicagoMar 30, 2021FKRP NM_024301.4 ex 4 p.Phe56Glyfs*6 (c.162_165dup): This variant has been reported in the literature in at least one individual with autosomal congenital muscular dystrophy (Brockington 2001 PMID:11592034). This variant is present in 0.001% (2/104602) of European alleles in the Genome Aggregation Database (https://gnomad.broadinstitute.org/variant/19-47258867-C-CGGGA) and is present in ClinVar, with several labs classifying this variant as pathogenic (Variation ID:282866). Evolutionary conservation and computational predictive tools for this variant are limited or unavailable. This variant creates a premature stop codon 6 amino acids downstream from this location which results in an absent or abnormal protein. Loss of function variants have been reported in association with disease for this gene (Thornhill 2008 PMID:18477595). In summary, this variant is classified as pathogenic based on the data above. -
Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A5 Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsAug 31, 2023- -
Walker-Warburg congenital muscular dystrophy Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpAug 29, 2023This variant is present in population databases (no rsID available, gnomAD 0.002%). For these reasons, this variant has been classified as Pathogenic. This variant disrupts a region of the FKRP protein in which other variant(s) (p.Q460*) have been determined to be pathogenic (PMID: 16476814; Invitae). This suggests that this is a clinically significant region of the protein, and that variants that disrupt it are likely to be disease-causing. ClinVar contains an entry for this variant (Variation ID: 282866). This premature translational stop signal has been observed in individuals with FKRP-related conditions (PMID: 11592034, 18160674). This sequence change creates a premature translational stop signal (p.Phe56Glyfs*6) in the FKRP gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 440 amino acid(s) of the FKRP protein. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs886042506; hg19: chr19-47258867; API