22-50528595-C-T
Variant summary
Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong
The NM_001953.5(TYMP):c.433G>A(p.Gly145Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000167 in 1,613,694 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
Consequence
NM_001953.5 missense
Scores
Clinical Significance
Conservation
Genome browser will be placed here
ACMG classification
Verdict is Pathogenic. Variant got 14 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000723 AC: 11AN: 152200Hom.: 0 Cov.: 33
GnomAD3 exomes AF: 0.0000160 AC: 4AN: 250760Hom.: 0 AF XY: 0.0000221 AC XY: 3AN XY: 135638
GnomAD4 exome AF: 0.0000109 AC: 16AN: 1461376Hom.: 0 Cov.: 32 AF XY: 0.0000110 AC XY: 8AN XY: 726984
GnomAD4 genome AF: 0.0000722 AC: 11AN: 152318Hom.: 0 Cov.: 33 AF XY: 0.0000537 AC XY: 4AN XY: 74480
ClinVar
Submissions by phenotype
Mitochondrial DNA depletion syndrome 1 Pathogenic:7
- -
- -
- -
- -
Variant summary: TYMP c.433G>A (p.Gly145Arg) results in a non-conservative amino acid change located in the Glycosyl transferase, family 3 (IPR000312) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 1.6e-05 in 250760 control chromosomes. c.433G>A has been reported in the literature in multiple individuals affected with Mitochondrial DNA Depletion Syndrome 1 (MNGIE type) (Example: Nishino_1999, Zaidman_2021). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 9924029, 33533561). Seven submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. All submitters classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
- -
- -
not provided Pathogenic:2
This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 145 of the TYMP protein (p.Gly145Arg). This variant is present in population databases (rs121913037, gnomAD 0.007%). This missense change has been observed in individuals with mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) (PMID: 9924029, 10852545, 16995425). It has also been observed to segregate with disease in related individuals. This variant is also known as G1419A. ClinVar contains an entry for this variant (Variation ID: 16655). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Not Available". The arginine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -
Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; In silico analysis is inconclusive as to whether the variant alters gene splicing. In the absence of RNA/functional studies, the actual effect of this sequence change is unknown.; This variant is associated with the following publications: (PMID: 19748572, 25525159, 9924029, 21820356, 16995425, 20301358, 18787099, 34288589) -
Mitochondrial neurogastrointestinal encephalomyopathy Pathogenic:1
- -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at