19-46755601-G-C

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 7P and 2B. PM1PM2PM5PP2BP4_Moderate

The NM_024301.5(FKRP):​c.151G>C​(p.Val51Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000688 in 1,453,536 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V51I) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

FKRP
NM_024301.5 missense

Scores

2
5
11

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.507

Publications

2 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 5 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 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 chr19-46755601-G-T is described in ClinVar as Pathogenic. ClinVar VariationId is 1455089.Status of the report is criteria_provided_single_submitter, 1 stars.
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=0.21916106).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FKRPNM_024301.5 linkc.151G>C p.Val51Leu missense_variant Exon 4 of 4 ENST00000318584.10 NP_077277.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FKRPENST00000318584.10 linkc.151G>C p.Val51Leu missense_variant Exon 4 of 4 1 NM_024301.5 ENSP00000326570.4

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000429
AC:
1
AN:
232940
AF XY:
0.00000788
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000567
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.88e-7
AC:
1
AN:
1453536
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
722736
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33324
American (AMR)
AF:
0.00
AC:
0
AN:
44042
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25924
East Asian (EAS)
AF:
0.0000254
AC:
1
AN:
39372
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85188
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50554
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1109308
Other (OTH)
AF:
0.00
AC:
0
AN:
60062
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cardiovascular phenotype Uncertain:1
Mar 24, 2023
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.V51L variant (also known as c.151G>C), located in coding exon 1 of the FKRP gene, results from a G to C substitution at nucleotide position 151. The valine at codon 51 is replaced by leucine, an amino acid with highly similar properties. This amino acid position is not well conserved in available vertebrate species. 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
Mar 18, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 51 of the FKRP protein (p.Val51Leu). This variant is present in population databases (no rsID available, gnomAD 0.006%). 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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This variant disrupts the p.Val51 amino acid residue in FKRP. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 27439679, 30107846). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. 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
0.22
BayesDel_addAF
Uncertain
0.012
T
BayesDel_noAF
Uncertain
-0.040
CADD
Benign
10
DANN
Benign
0.95
DEOGEN2
Benign
0.0
.;T;.;.;.;T;.;.;.;.;.;.;.;.;.;T
Eigen
Benign
-0.95
Eigen_PC
Benign
-0.99
FATHMM_MKL
Uncertain
0.89
D
LIST_S2
Benign
0.81
T;.;T;T;T;T;T;T;T;T;T;T;T;T;T;T
M_CAP
Uncertain
0.19
D
MetaRNN
Benign
0.22
T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Pathogenic
0.81
D
MutationAssessor
Benign
0.0
.;L;.;.;.;L;.;.;.;.;.;.;.;.;.;.
PhyloP100
0.51
PrimateAI
Uncertain
0.68
T
PROVEAN
Benign
0.0
.;N;.;.;.;N;.;.;.;.;.;.;.;.;.;.
REVEL
Benign
0.0
Sift
Pathogenic
0.0
.;D;.;.;.;D;.;.;.;.;.;.;.;.;.;.
Sift4G
Benign
0.073
T;T;D;D;D;T;D;D;D;D;D;D;D;D;D;D
Vest4
0.0
ClinPred
0.064
T
GERP RS
-3.0
Varity_R
0.36
gMVP
0.63
Mutation Taster
=65/35
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: rs769377092; hg19: chr19-47258858; API