20-4699915-T-G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BS1_SupportingBS2

The NM_000311.5(PRNP):​c.695T>G​(p.Met232Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000115 in 1,613,938 control chromosomes in the GnomAD database, including 1 homozygotes. 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. M232I) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00012 ( 1 hom. )

Consequence

PRNP
NM_000311.5 missense

Scores

1
8
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 0.268

Publications

87 publications found
Variant links:
Genes affected
PRNP (HGNC:9449): (prion protein (Kanno blood group)) The protein encoded by this gene is a membrane glycosylphosphatidylinositol-anchored glycoprotein that tends to aggregate into rod-like structures. The encoded protein contains a highly unstable region of five tandem octapeptide repeats. This gene is found on chromosome 20, approximately 20 kbp upstream of a gene which encodes a biochemically and structurally similar protein to the one encoded by this gene. Mutations in the repeat region as well as elsewhere in this gene have been associated with Creutzfeldt-Jakob disease, fatal familial insomnia, Gerstmann-Straussler disease, Huntington disease-like 1, and kuru. An overlapping open reading frame has been found for this gene that encodes a smaller, structurally unrelated protein, AltPrp. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2014]
PRNP Gene-Disease associations (from GenCC):
  • Gerstmann-Straussler-Scheinker syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Genomics England PanelApp, Orphanet
  • Huntington disease-like 1
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
  • inherited Creutzfeldt-Jakob disease
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • familial Alzheimer-like prion disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • fatal familial insomnia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • PrP systemic amyloidosis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BS1
Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.0000657 (10/152188) while in subpopulation EAS AF = 0.00194 (10/5166). AF 95% confidence interval is 0.00105. There are 0 homozygotes in GnomAd4. There are 7 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAd4 at 10 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
PRNPNM_000311.5 linkc.695T>G p.Met232Arg missense_variant Exon 2 of 2 ENST00000379440.9 NP_000302.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
PRNPENST00000379440.9 linkc.695T>G p.Met232Arg missense_variant Exon 2 of 2 1 NM_000311.5 ENSP00000368752.4
PRNPENST00000424424.2 linkc.695T>G p.Met232Arg missense_variant Exon 2 of 2 1 ENSP00000411599.2
PRNPENST00000430350.2 linkc.695T>G p.Met232Arg missense_variant Exon 2 of 2 1 ENSP00000399376.2
PRNPENST00000457586.2 linkc.695T>G p.Met232Arg missense_variant Exon 2 of 2 1 ENSP00000415284.2

Frequencies

GnomAD3 genomes
AF:
0.0000658
AC:
10
AN:
152070
Hom.:
0
Cov.:
32
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:
0.00193
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000597
AC:
15
AN:
251220
AF XY:
0.0000442
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000816
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000120
AC:
175
AN:
1461750
Hom.:
1
Cov.:
32
AF XY:
0.000117
AC XY:
85
AN XY:
727144
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00436
AC:
173
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86230
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111916
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.491
Heterozygous variant carriers
0
12
24
35
47
59
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
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
AF:
0.0000657
AC:
10
AN:
152188
Hom.:
0
Cov.:
32
AF XY:
0.0000941
AC XY:
7
AN XY:
74384
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41524
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00194
AC:
10
AN:
5166
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4806
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68006
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.485
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:
0.00000756
ExAC
AF:
0.0000824
AC:
10
Asia WGS
AF:
0.00231
AC:
8
AN:
3478

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Huntington disease-like 1 Uncertain:2
Nov 01, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 232 of the PRNP protein (p.Met232Arg). This variant is present in population databases (rs74315409, gnomAD 0.09%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with Creutzfeldt-Jakob disease (PMID: 19422533, 19422537, 21983261, 23320809, 25818675). ClinVar contains an entry for this variant (Variation ID: 13406). 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 not expected to disrupt PRNP protein function with a negative predictive value of 80%. 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. -

May 28, 2019
Mendelics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Gerstmann-Straussler-Scheinker syndrome;C0206042:Fatal familial insomnia;C0751254:Inherited Creutzfeldt-Jakob disease;C1847650:Spongiform encephalopathy with neuropsychiatric features;C1855588:Kuru, susceptibility to;C1864112:Huntington disease-like 1 Uncertain:1
Dec 02, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inherited Creutzfeldt-Jakob disease Uncertain:1
Feb 01, 2012
OMIM
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.14
BayesDel_addAF
Uncertain
0.018
T
BayesDel_noAF
Pathogenic
0.19
CADD
Benign
14
DANN
Benign
0.77
DEOGEN2
Benign
0.28
T;T;T
Eigen
Benign
-0.56
Eigen_PC
Benign
-0.69
FATHMM_MKL
Benign
0.17
N
LIST_S2
Uncertain
0.96
.;D;D
M_CAP
Uncertain
0.13
D
MetaRNN
Uncertain
0.44
T;T;T
MetaSVM
Uncertain
-0.25
T
MutationAssessor
Benign
1.2
L;L;.
PhyloP100
0.27
PrimateAI
Benign
0.31
T
PROVEAN
Benign
-1.1
N;N;N
REVEL
Uncertain
0.59
Sift
Uncertain
0.0010
D;D;D
Sift4G
Uncertain
0.0070
D;D;D
Polyphen
0.17
B;B;.
Vest4
0.73
MVP
0.99
MPC
0.98
ClinPred
0.055
T
GERP RS
1.1
Varity_R
0.48
gMVP
0.66
Mutation Taster
=16/84
disease causing

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: rs74315409; hg19: chr20-4680561; API