rs1449983261

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2PP2BP4

The NM_024301.5(FKRP):​c.446G>A​(p.Arg149His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000066 in 1,514,872 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000044 ( 0 hom. )

Consequence

FKRP
NM_024301.5 missense

Scores

1
5
13

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 1.93

Publications

0 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: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
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.
BP4
Computational evidence support a benign effect (MetaRNN=0.2945698).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FKRPNM_024301.5 linkc.446G>A p.Arg149His 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.446G>A p.Arg149His missense_variant Exon 4 of 4 1 NM_024301.5 ENSP00000326570.4 Q9H9S5

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152220
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00
AC:
0
AN:
114180
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000440
AC:
6
AN:
1362652
Hom.:
0
Cov.:
32
AF XY:
0.00000596
AC XY:
4
AN XY:
670816
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
30548
American (AMR)
AF:
0.00
AC:
0
AN:
32546
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
23734
East Asian (EAS)
AF:
0.00
AC:
0
AN:
35190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
76274
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
33676
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5458
European-Non Finnish (NFE)
AF:
0.00000562
AC:
6
AN:
1068352
Other (OTH)
AF:
0.00
AC:
0
AN:
56874
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152220
Hom.:
0
Cov.:
33
AF XY:
0.0000269
AC XY:
2
AN XY:
74362
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41466
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4838
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000189

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive limb-girdle muscular dystrophy type 2I Uncertain:1
Aug 27, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Cardiovascular phenotype Uncertain:1
Jan 21, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R149H variant (also known as c.446G>A), located in coding exon 1 of the FKRP gene, results from a G to A substitution at nucleotide position 446. The arginine at codon 149 is replaced by histidine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Walker-Warburg congenital muscular dystrophy Uncertain:1
Aug 30, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine with histidine at codon 149 of the FKRP protein (p.Arg149His). The arginine residue is moderately conserved and there is a small physicochemical difference between arginine and histidine. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This variant has not been reported in the literature in individuals affected with FKRP-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Uncertain
0.063
T
BayesDel_noAF
Benign
-0.15
CADD
Benign
19
DANN
Benign
0.95
DEOGEN2
Benign
0.24
.;T;T;.
Eigen
Benign
-0.50
Eigen_PC
Benign
-0.52
FATHMM_MKL
Benign
0.11
N
LIST_S2
Benign
0.78
T;.;T;T
M_CAP
Uncertain
0.26
D
MetaRNN
Benign
0.29
T;T;T;T
MetaSVM
Uncertain
0.65
D
MutationAssessor
Benign
0.55
.;N;N;.
PhyloP100
1.9
PrimateAI
Pathogenic
0.85
D
PROVEAN
Benign
-0.57
.;N;N;.
REVEL
Uncertain
0.35
Sift
Benign
0.18
.;T;T;.
Sift4G
Uncertain
0.037
D;T;T;D
Polyphen
0.78
.;P;P;.
Vest4
0.078, 0.094
MutPred
0.32
Loss of MoRF binding (P = 0.0166);Loss of MoRF binding (P = 0.0166);Loss of MoRF binding (P = 0.0166);.;
MVP
0.98
MPC
1.2
ClinPred
0.22
T
GERP RS
1.2
Varity_R
0.18
gMVP
0.46
Mutation Taster
=81/19
polymorphism

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: rs1449983261; hg19: chr19-47259153; COSMIC: COSV105897086; COSMIC: COSV105897086; API