1-183292842-G-A

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM2PP2PP3_Moderate

The NM_015039.4(NMNAT2):​c.190C>T​(p.Arg64Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,894 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. R64Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

NMNAT2
NM_015039.4 missense

Scores

10
7
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.42

Publications

3 publications found
Variant links:
Genes affected
NMNAT2 (HGNC:16789): (nicotinamide nucleotide adenylyltransferase 2) This gene product belongs to the nicotinamide mononucleotide adenylyltransferase (NMNAT) enzyme family, members of which catalyze an essential step in NAD (NADP) biosynthetic pathway. Unlike the other human family member, which is localized to the nucleus, and is ubiquitously expressed; this enzyme is cytoplasmic, and is predominantly expressed in the brain. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 5 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 1 curated pathogenic missense variants (we use a threshold of 10). The gene has 0 curated benign missense variants. Gene score misZ: 2.1005 (below the threshold of 3.09). Trascript score misZ: 2.0325 (below the threshold of 3.09).
PP3
MetaRNN computational evidence supports a deleterious effect, 0.849

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
NMNAT2NM_015039.4 linkc.190C>T p.Arg64Trp missense_variant Exon 3 of 11 ENST00000287713.7 NP_055854.1 Q9BZQ4-1
NMNAT2NM_170706.4 linkc.175C>T p.Arg59Trp missense_variant Exon 3 of 11 NP_733820.1 Q9BZQ4-2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
NMNAT2ENST00000287713.7 linkc.190C>T p.Arg64Trp missense_variant Exon 3 of 11 1 NM_015039.4 ENSP00000287713.6 Q9BZQ4-1
NMNAT2ENST00000294868.8 linkc.175C>T p.Arg59Trp missense_variant Exon 3 of 11 1 ENSP00000294868.4 Q9BZQ4-2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152146
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000120
AC:
3
AN:
250968
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000290
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000479
AC:
7
AN:
1461748
Hom.:
0
Cov.:
31
AF XY:
0.00000825
AC XY:
6
AN XY:
727170
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33468
American (AMR)
AF:
0.0000224
AC:
1
AN:
44712
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39692
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86226
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53410
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000360
AC:
4
AN:
1111958
Other (OTH)
AF:
0.00
AC:
0
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.468
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

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
AF:
0.00000657
AC:
1
AN:
152146
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74304
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41440
American (AMR)
AF:
0.00
AC:
0
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
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:
10600
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68038
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
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
May 14, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.190C>T (p.R64W) alteration is located in exon 3 (coding exon 3) of the NMNAT2 gene. This alteration results from a C to T substitution at nucleotide position 190, causing the arginine (R) at amino acid position 64 to be replaced by a tryptophan (W). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.61
BayesDel_addAF
Pathogenic
0.35
D
BayesDel_noAF
Pathogenic
0.44
CADD
Pathogenic
28
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.74
.;D
Eigen
Uncertain
0.64
Eigen_PC
Uncertain
0.62
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Pathogenic
0.99
D;D
M_CAP
Pathogenic
0.33
D
MetaRNN
Pathogenic
0.85
D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Uncertain
2.0
.;M
PhyloP100
3.4
PrimateAI
Pathogenic
0.81
D
PROVEAN
Uncertain
-2.4
N;N
REVEL
Pathogenic
0.78
Sift
Benign
0.058
T;T
Sift4G
Uncertain
0.013
D;T
Polyphen
1.0
D;D
Vest4
0.82
MutPred
0.46
.;Loss of disorder (P = 0.0227);
MVP
0.97
MPC
1.9
ClinPred
0.86
D
GERP RS
5.2
Varity_R
0.31
gMVP
0.88
Mutation Taster
=27/73
disease causing

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: rs201746612; hg19: chr1-183261977; COSMIC: COSV54268495; COSMIC: COSV54268495; API