rs756511637

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_018109.4(MTPAP):​c.1624A>G​(p.Thr542Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000564 in 1,614,098 control chromosomes in the GnomAD database, with no homozygous occurrence. 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000058 ( 0 hom. )

Consequence

MTPAP
NM_018109.4 missense

Scores

19

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 0.367

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 -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.041933775).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MTPAPNM_018109.4 linkc.1624A>G p.Thr542Ala 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.1624A>G p.Thr542Ala missense_variant Exon 9 of 9 1 NM_018109.4 ENSP00000263063.3 Q9NVV4-1
MTPAPENST00000488290.5 linkn.3379A>G non_coding_transcript_exon_variant Exon 17 of 17 2

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152228
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000278
AC:
7
AN:
251418
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000581
AC:
85
AN:
1461870
Hom.:
0
Cov.:
31
AF XY:
0.0000564
AC XY:
41
AN XY:
727240
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.0000447
AC:
2
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:
0.00
AC:
0
AN:
86256
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:
0.0000665
AC:
74
AN:
1111996
Other (OTH)
AF:
0.000149
AC:
9
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
5
11
16
22
27
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000394
AC:
6
AN:
152228
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74370
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41464
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5204
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.542
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:
0.0000508
Hom.:
0
Bravo
AF:
0.0000302
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.000164
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3
May 03, 2023
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 uninformative in assessment of its pathogenicity (http://gnomad.broadinstitute.org). Computational tools predict that this variant is not damaging. -

Apr 23, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Nov 11, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with alanine, which is neutral and non-polar, at codon 542 of the MTPAP protein (p.Thr542Ala). This variant is present in population databases (rs756511637, gnomAD 0.006%). 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: 2182204). An algorithm developed to predict the effect of missense changes on protein structure and function outputs the following: PolyPhen-2: "Benign". The alanine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Spastic ataxia 4 Uncertain:1
Sep 09, 2022
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

- -

Inborn genetic diseases Benign:1
Feb 13, 2025
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.061
BayesDel_addAF
Benign
-0.52
T
BayesDel_noAF
Benign
-0.81
CADD
Benign
0.18
DANN
Benign
0.19
DEOGEN2
Benign
0.0096
T
Eigen
Benign
-1.7
Eigen_PC
Benign
-1.7
FATHMM_MKL
Benign
0.055
N
LIST_S2
Benign
0.21
T
M_CAP
Benign
0.0038
T
MetaRNN
Benign
0.042
T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
-1.1
N
PhyloP100
0.37
PrimateAI
Benign
0.25
T
PROVEAN
Benign
-0.35
N
REVEL
Benign
0.012
Sift
Benign
0.87
T
Sift4G
Benign
0.86
T
Polyphen
0.0
B
Vest4
0.016
MutPred
0.25
Loss of loop (P = 0.0203);
MVP
0.26
MPC
0.35
ClinPred
0.018
T
GERP RS
-2.9
Varity_R
0.014
gMVP
0.082
Mutation Taster
=98/2
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: rs756511637; hg19: chr10-30602663; API