chr19-46756814-C-A

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1PM2PM5PP2PP3_ModeratePP5_Very_Strong

The NM_024301.5(FKRP):​c.1364C>A​(p.Ala455Asp) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A455S) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

FKRP
NM_024301.5 missense

Scores

7
9
3

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:10

Conservation

PhyloP100: 4.85

Publications

20 publications found
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]
FKRP Gene-Disease associations (from GenCC):
  • autosomal recessive limb-girdle muscular dystrophy type 2I
    Inheritance: 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 A5
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Genomics England PanelApp, G2P, Ambry Genetics
  • muscular dystrophy-dystroglycanopathy type B5
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Myriad Women’s Health, Labcorp Genetics (formerly Invitae)
  • myopathy caused by variation in FKRP
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • congenital muscular dystrophy with cerebellar involvement
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • congenital muscular dystrophy with intellectual disability
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • congenital muscular dystrophy without intellectual disability
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • muscle-eye-brain disease
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • muscular dystrophy-dystroglycanopathy, type A
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 17 ACMG points.

PM1
In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 15 uncertain in NM_024301.5
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr19-46756813-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 577969.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 46 curated pathogenic missense variants (we use a threshold of 10). The gene has 2 curated benign missense variants. Gene score misZ: 1.8498 (below the threshold of 3.09). Trascript score misZ: -2.4986 (below the threshold of 3.09). GenCC associations: The gene is linked to autosomal recessive limb-girdle muscular dystrophy type 2I, muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A5, congenital muscular dystrophy with intellectual disability, muscular dystrophy-dystroglycanopathy, type A, muscle-eye-brain disease, congenital muscular dystrophy with cerebellar involvement, myopathy caused by variation in FKRP, muscular dystrophy-dystroglycanopathy type B5, congenital muscular dystrophy without intellectual disability.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.904
PP5
Variant 19-46756814-C-A is Pathogenic according to our data. Variant chr19-46756814-C-A is described in ClinVar as Pathogenic. ClinVar VariationId is 4226.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FKRPNM_024301.5 linkc.1364C>A p.Ala455Asp missense_variant Exon 4 of 4 ENST00000318584.10 NP_077277.1 Q9H9S5A0A024R0R7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FKRPENST00000318584.10 linkc.1364C>A p.Ala455Asp missense_variant Exon 4 of 4 1 NM_024301.5 ENSP00000326570.4 Q9H9S5
FKRPENST00000391909.7 linkc.1364C>A p.Ala455Asp missense_variant Exon 4 of 4 2 ENSP00000375776.2 Q9H9S5
FKRPENST00000597339.5 linkn.247-5019C>A intron_variant Intron 3 of 3 5
FKRPENST00000600646.5 linkn.247+8149C>A intron_variant Intron 3 of 3 3

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
1447190
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
718928
African (AFR)
AF:
0.00
AC:
0
AN:
33172
American (AMR)
AF:
0.00
AC:
0
AN:
42598
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25774
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38996
South Asian (SAS)
AF:
0.00
AC:
0
AN:
84426
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51026
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5750
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1105580
Other (OTH)
AF:
0.00
AC:
0
AN:
59868
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.0000107
Hom.:
0

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:10
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2I Pathogenic:3
Sep 14, 2015
Athena Diagnostics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 03, 2018
Counsyl
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

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. -

Sep 26, 2019
Biochemical Molecular Genetic Laboratory, King Abdulaziz Medical City
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

not provided Pathogenic:3
Dec 16, 2020
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed in large population cohorts (Lek et al., 2016); The majority of missense variants in this gene are considered pathogenic (Stenson et al., 2014); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 33101984, 31130284, 31268217, 16368217, 28454995, 14652796, 22908982, 23420653, 15574464, 23894383, 18671187, 19955119) -

Apr 28, 2017
Eurofins Ntd Llc (ga)
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 08, 2022
Revvity Omics, Revvity
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Muscular dystrophy-dystroglycanopathy type B5 Pathogenic:2
Feb 01, 2004
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Mar 25, 2024
Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A5 Pathogenic:1
Feb 04, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Walker-Warburg congenital muscular dystrophy Pathogenic:1
May 25, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects FKRP function (PMID: 15574464, 19955119). 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) performed at Invitae indicates that this missense variant is expected to disrupt FKRP protein function. ClinVar contains an entry for this variant (Variation ID: 4226). This missense change has been observed in individuals with congenital muscular dystrophy, limb-girdle muscular dystrophy and muscle-eye brain disease (PMID: 14652796, 16368217, 18671187, 23420653, 23894383). It has also been observed to segregate with disease in related individuals. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces alanine, which is neutral and non-polar, with aspartic acid, which is acidic and polar, at codon 455 of the FKRP protein (p.Ala455Asp). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.96
BayesDel_addAF
Pathogenic
0.47
D
BayesDel_noAF
Pathogenic
0.44
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.68
D;D
Eigen
Uncertain
0.55
Eigen_PC
Uncertain
0.56
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Benign
0.81
.;T
M_CAP
Pathogenic
0.55
D
MetaRNN
Pathogenic
0.90
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Benign
2.0
M;M
PhyloP100
4.9
PrimateAI
Uncertain
0.67
T
PROVEAN
Uncertain
-4.0
D;D
REVEL
Pathogenic
0.82
Sift
Uncertain
0.0050
D;D
Sift4G
Uncertain
0.014
D;D
Polyphen
0.99
D;D
Vest4
0.75
MutPred
0.60
Gain of relative solvent accessibility (P = 0.0217);Gain of relative solvent accessibility (P = 0.0217);
MVP
0.99
MPC
1.9
ClinPred
0.99
D
GERP RS
5.4
Varity_R
0.82
gMVP
0.80
Mutation Taster
=4/96
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs28937903; hg19: chr19-47260071; API