NM_018109.4:c.1643A>C

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_018109.4(MTPAP):​c.1643A>C​(p.Lys548Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000768 in 1,614,246 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000082 ( 1 hom. )

Consequence

MTPAP
NM_018109.4 missense

Scores

19

Clinical Significance

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

Conservation

PhyloP100: 0.0320

Publications

0 publications found
Variant links:
Genes affected
MTPAP (HGNC:25532): (mitochondrial poly(A) polymerase) The protein encoded by this gene is a member of the DNA polymerase type-B-like family. This enzyme synthesizes the 3' poly(A) tail of mitochondrial transcripts and plays a role in replication-dependent histone mRNA degradation.[provided by RefSeq, Jan 2011]
MTPAP Gene-Disease associations (from GenCC):
  • mitochondrial disease
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • spastic ataxia 4
    Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -4 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.025054514).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MTPAPNM_018109.4 linkc.1643A>C p.Lys548Thr missense_variant Exon 9 of 9 ENST00000263063.9 NP_060579.3 Q9NVV4-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MTPAPENST00000263063.9 linkc.1643A>C p.Lys548Thr missense_variant Exon 9 of 9 1 NM_018109.4 ENSP00000263063.3 Q9NVV4-1
MTPAPENST00000488290.5 linkn.3398A>C non_coding_transcript_exon_variant Exon 17 of 17 2

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152254
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:
0.00
Gnomad SAS
AF:
0.000414
Gnomad FIN
AF:
0.000188
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000159
AC:
40
AN:
251414
AF XY:
0.000228
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.0000924
Gnomad NFE exome
AF:
0.0000792
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000821
AC:
120
AN:
1461874
Hom.:
1
Cov.:
31
AF XY:
0.000113
AC XY:
82
AN XY:
727238
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.000835
AC:
72
AN:
86258
European-Finnish (FIN)
AF:
0.0000562
AC:
3
AN:
53420
Middle Eastern (MID)
AF:
0.00139
AC:
8
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000324
AC:
36
AN:
1111996
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.478
Heterozygous variant carriers
0
10
19
29
38
48
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:
0.0000263
AC:
4
AN:
152372
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74520
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41590
American (AMR)
AF:
0.00
AC:
0
AN:
15310
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.000414
AC:
2
AN:
4828
European-Finnish (FIN)
AF:
0.000188
AC:
2
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
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

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:
0.0000920
Hom.:
0
Bravo
AF:
0.0000378
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000165
AC:
20
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

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

Submissions by phenotype

not provided Uncertain:2
Jun 27, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces lysine, which is basic and polar, with threonine, which is neutral and polar, at codon 548 of the MTPAP protein (p.Lys548Thr). This variant is present in population databases (rs372986653, gnomAD 0.09%). This variant has not been reported in the literature in individuals affected with MTPAP-related conditions. ClinVar contains an entry for this variant (Variation ID: 447742). 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. -

Aug 13, 2024
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Available data are insufficient to determine the clinical significance of the variant at this time. The frequency of this variant in the general population is higher than would generally be expected for pathogenic variants in this gene. (http://gnomad.broadinstitute.org) Polyphen and MutationTaster predict this amino acid change may be benign. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.082
BayesDel_addAF
Benign
-0.52
T
BayesDel_noAF
Benign
-0.60
CADD
Benign
0.68
DANN
Benign
0.43
DEOGEN2
Benign
0.017
T
Eigen
Benign
-1.3
Eigen_PC
Benign
-1.5
FATHMM_MKL
Benign
0.32
N
LIST_S2
Benign
0.22
T
M_CAP
Benign
0.014
T
MetaRNN
Benign
0.025
T
MetaSVM
Benign
-0.89
T
MutationAssessor
Benign
1.9
L
PhyloP100
0.032
PrimateAI
Benign
0.25
T
PROVEAN
Benign
-0.64
N
REVEL
Benign
0.10
Sift
Benign
0.090
T
Sift4G
Benign
0.23
T
Polyphen
0.11
B
Vest4
0.13
MVP
0.31
MPC
0.50
ClinPred
0.058
T
GERP RS
-6.5
Varity_R
0.024
gMVP
0.19
Mutation Taster
=93/7
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.060
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: rs372986653; hg19: chr10-30602644; API