NM_001953.5:c.665A>G

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM2PP3_ModeratePP5_Very_Strong

The NM_001953.5(TYMP):​c.665A>G​(p.Lys222Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000118 in 1,613,446 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

TYMP
NM_001953.5 missense

Scores

10
7
2

Clinical Significance

Likely pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 2.55
Variant links:
Genes affected
TYMP (HGNC:3148): (thymidine phosphorylase) This gene encodes an angiogenic factor which promotes angiogenesis in vivo and stimulates the in vitro growth of a variety of endothelial cells. It has a highly restricted target cell specificity acting only on endothelial cells. Mutations in this gene have been associated with mitochondrial neurogastrointestinal encephalomyopathy. Multiple alternatively spliced transcript variants have been identified. [provided by RefSeq, Apr 2012]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.882
PP5
Variant 22-50527265-T-C is Pathogenic according to our data. Variant chr22-50527265-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 16656.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TYMPNM_001953.5 linkc.665A>G p.Lys222Arg missense_variant Exon 6 of 10 ENST00000252029.8 NP_001944.1 P19971-1E5KRG5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TYMPENST00000252029.8 linkc.665A>G p.Lys222Arg missense_variant Exon 6 of 10 1 NM_001953.5 ENSP00000252029.3 P19971-1

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152176
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.000338
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000120
AC:
3
AN:
250636
Hom.:
0
AF XY:
0.0000147
AC XY:
2
AN XY:
135826
show subpopulations
Gnomad AFR exome
AF:
0.000186
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000342
AC:
5
AN:
1461270
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
726952
show subpopulations
Gnomad4 AFR exome
AF:
0.000149
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000920
AC:
14
AN:
152176
Hom.:
0
Cov.:
33
AF XY:
0.0000673
AC XY:
5
AN XY:
74340
show subpopulations
Gnomad4 AFR
AF:
0.000338
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000718
ESP6500AA
AF:
0.000454
AC:
2
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Mitochondrial DNA depletion syndrome 1 Pathogenic:3
Mar 29, 2024
Baylor Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jun 01, 2000
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Jan 14, 2016
GeneReviews
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

not provided Pathogenic:2
Sep 09, 2016
GeneDx
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The K222R variant in the TYMP gene has previously been reported association with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) syndrome in an individual who was also heterozygous for frameshift variant in TYMP although the phase of these variants was not determined (Giordano et al., 2008). The K222R variant was not observed at any significant frequency in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The K222R variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. This substitution occurs at a position that is conserved across species and is predicted to be involved in phosphate binding within the activite site of the thymidine phosphorylase enzyme (Nishino et al., 1999; Pugmire et al., 1998). Additionally, in silico analysis predicts this variant is probably damaging to the protein structure/function. Therefore, this variant is likely pathogenic; however, the possibility that it is benign cannot be excluded. -

Aug 21, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant is also known as A2744G. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on TYMP protein function. ClinVar contains an entry for this variant (Variation ID: 16656). This missense change has been observed in individual(s) with mitochondrial neurogastrointestinal encephalopathy (PMID: 9924029). This variant is present in population databases (rs149977726, gnomAD 0.03%). This sequence change replaces lysine, which is basic and polar, with arginine, which is basic and polar, at codon 222 of the TYMP protein (p.Lys222Arg). -

Mitochondrial neurogastrointestinal encephalomyopathy Pathogenic:1
Jun 29, 2021
Natera, Inc.
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.72
BayesDel_addAF
Pathogenic
0.19
D
BayesDel_noAF
Pathogenic
0.33
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.93
D;.;D;D;D
Eigen
Uncertain
0.52
Eigen_PC
Uncertain
0.33
FATHMM_MKL
Uncertain
0.87
D
LIST_S2
Uncertain
0.93
.;D;.;D;T
M_CAP
Pathogenic
0.77
D
MetaRNN
Pathogenic
0.88
D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.1
H;H;H;H;.
PrimateAI
Benign
0.43
T
PROVEAN
Uncertain
-2.8
D;D;D;D;D
REVEL
Pathogenic
0.79
Sift
Pathogenic
0.0
D;D;D;D;D
Sift4G
Uncertain
0.011
D;D;D;D;D
Polyphen
1.0
D;.;D;D;.
Vest4
0.71
MVP
0.95
MPC
1.0
ClinPred
0.99
D
GERP RS
3.7
Varity_R
0.96
gMVP
0.87

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs149977726; hg19: chr22-50965694; API