rs72624967

Variant summary

Our verdict is Benign. The variant received -10 ACMG points: 1P and 11B. PP3BP4_ModerateBP6BS1BS2

The NM_000883.4(IMPDH1):​c.1489C>T​(p.Arg497Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000263 in 1,613,638 control chromosomes in the GnomAD database, including 6 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R497Q) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0013 ( 3 hom., cov: 32)
Exomes 𝑓: 0.00015 ( 3 hom. )

Consequence

IMPDH1
NM_000883.4 missense

Scores

8
8
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:3

Conservation

PhyloP100: 3.54

Publications

4 publications found
Variant links:
Genes affected
IMPDH1 (HGNC:6052): (inosine monophosphate dehydrogenase 1) The protein encoded by this gene acts as a homotetramer to regulate cell growth. The encoded protein is an enzyme that catalyzes the synthesis of xanthine monophosphate (XMP) from inosine-5'-monophosphate (IMP). This is the rate-limiting step in the de novo synthesis of guanine nucleotides. Defects in this gene are a cause of retinitis pigmentosa type 10 (RP10). Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2008]
IMPDH1 Gene-Disease associations (from GenCC):
  • inherited retinal dystrophy
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • Leber congenital amaurosis 11
    Inheritance: AD Classification: DEFINITIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • retinitis pigmentosa 10
    Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
  • Leber congenital amaurosis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • retinitis pigmentosa
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -10 ACMG points.

PP3
Multiple lines of computational evidence support a deleterious effect 8: AlphaMissense, BayesDel_noAF, Cadd, Dann, PrimateAI, PROVEAN, REVEL, REVEL [when max_spliceai, FATHMM_MKL, MetaRNN, MutationTaster, phyloP100way_vertebrate was below the threshold]
BP4
Computational evidence support a benign effect (MetaRNN=0.08491546).
BP6
Variant 7-128394950-G-A is Benign according to our data. Variant chr7-128394950-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 767527.
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00133 (202/152238) while in subpopulation AFR AF = 0.00453 (188/41524). AF 95% confidence interval is 0.004. There are 3 homozygotes in GnomAd4. There are 111 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High AC in GnomAd4 at 202 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
IMPDH1NM_000883.4 linkc.1489C>T p.Arg497Trp missense_variant Exon 14 of 17 ENST00000338791.11 NP_000874.2 P20839-6B3KRZ3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
IMPDH1ENST00000338791.11 linkc.1489C>T p.Arg497Trp missense_variant Exon 14 of 17 2 NM_000883.4 ENSP00000345096.6 P20839-6

Frequencies

GnomAD3 genomes
AF:
0.00133
AC:
203
AN:
152120
Hom.:
3
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00456
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000720
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:
0.0000147
Gnomad OTH
AF:
0.000957
GnomAD2 exomes
AF:
0.000339
AC:
85
AN:
251006
AF XY:
0.000258
show subpopulations
Gnomad AFR exome
AF:
0.00444
Gnomad AMR exome
AF:
0.000260
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.000153
AC:
223
AN:
1461400
Hom.:
3
Cov.:
33
AF XY:
0.000135
AC XY:
98
AN XY:
727000
show subpopulations
African (AFR)
AF:
0.00484
AC:
162
AN:
33478
American (AMR)
AF:
0.000246
AC:
11
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000756
AC:
3
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86244
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53058
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5688
European-Non Finnish (NFE)
AF:
0.0000342
AC:
38
AN:
1111998
Other (OTH)
AF:
0.000133
AC:
8
AN:
60376
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
16
32
47
63
79
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
10
20
30
40
50
<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:
0.00133
AC:
202
AN:
152238
Hom.:
3
Cov.:
32
AF XY:
0.00149
AC XY:
111
AN XY:
74438
show subpopulations
African (AFR)
AF:
0.00453
AC:
188
AN:
41524
American (AMR)
AF:
0.000719
AC:
11
AN:
15294
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
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:
0.0000147
AC:
1
AN:
68016
Other (OTH)
AF:
0.000947
AC:
2
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.486
Heterozygous variant carriers
0
11
22
34
45
56
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:
0.000676
Hom.:
0
Bravo
AF:
0.00151
ESP6500AA
AF:
0.00386
AC:
17
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000371
AC:
45
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:1
Dec 18, 2018
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The IMPDH1 c.1489C>T; p.Arg497Trp variant (rs72624967), to our knowledge, is not reported in the medical literature or gene-specific databases. The variant is reported in the African population with an allele frequency of 0.5% (121/24928 alleles, including 1 homozygote). The amino acid at this position is highly conserved and computational algorithms (PolyPhen-2, SIFT) predict this variant is deleterious. Although the increased allele frequency indicates the variant may not be clinically significant, there is insufficient evidence to classify the variant with certainty. -

IMPDH1-related disorder Benign:1
Sep 23, 2019
PreventionGenetics, part of Exact Sciences
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

not provided Benign:1
Jan 14, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Retinal dystrophy Benign:1
Oct 01, 2023
Dept Of Ophthalmology, Nagoya University
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:research

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.90
BayesDel_addAF
Uncertain
0.074
D
BayesDel_noAF
Pathogenic
0.34
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.54
.;.;.;.;D;.;D;.
Eigen
Uncertain
0.67
Eigen_PC
Uncertain
0.62
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Uncertain
0.89
D;D;D;D;D;D;.;D
M_CAP
Uncertain
0.21
D
MetaRNN
Benign
0.085
T;T;T;T;T;T;T;T
MetaSVM
Uncertain
0.28
D
PhyloP100
3.5
PrimateAI
Pathogenic
0.87
D
PROVEAN
Pathogenic
-7.7
D;D;D;D;.;D;D;D
REVEL
Pathogenic
0.85
Sift
Pathogenic
0.0
D;D;D;D;.;D;D;D
Sift4G
Pathogenic
0.0
D;D;D;D;D;D;D;D
Polyphen
1.0
.;.;D;.;.;D;.;.
Vest4
0.91
MVP
0.84
MPC
1.3
ClinPred
0.14
T
GERP RS
4.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
2.7
gMVP
0.96
Mutation Taster
=76/24
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs72624967; hg19: chr7-128035004; COSMIC: COSV99053345; COSMIC: COSV99053345; API