22-50526000-C-T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1_ModeratePM2PP5_Very_Strong

The NM_001953.5(TYMP):​c.1300+1G>A variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000698 in 1,432,820 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 34)
Exomes 𝑓: 0.0000070 ( 0 hom. )

Consequence

TYMP
NM_001953.5 splice_donor, intron

Scores

1
4
2
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 3.21

Publications

0 publications found
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]
SCO2 (HGNC:10604): (synthesis of cytochrome C oxidase 2) Cytochrome c oxidase (COX) catalyzes the transfer of electrons from cytochrome c to molecular oxygen, which helps to maintain the proton gradient across the inner mitochondrial membrane that is necessary for aerobic ATP production. Human COX is a multimeric protein complex that requires several assembly factors; this gene encodes one of the COX assembly factors. The encoded protein is a metallochaperone that is involved in the biogenesis of cytochrome c oxidase subunit II. Mutations in this gene are associated with fatal infantile encephalocardiomyopathy and myopia 6. [provided by RefSeq, Oct 2014]
SCO2 Gene-Disease associations (from GenCC):
  • cardioencephalomyopathy, fatal infantile, due to cytochrome c oxidase deficiency 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • Leigh syndrome
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • myopia 6
    Inheritance: AD Classification: STRONG Submitted by: G2P
  • autosomal recessive axonal charcot-marie-tooth disease due to copper metabolism defect
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.09730849 fraction of the gene. Cryptic splice site detected, with MaxEntScore 3.5, offset of -22, new splice context is: gacGTgggt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 22-50526000-C-T is Pathogenic according to our data. Variant chr22-50526000-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 223069.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.1300+1G>A splice_donor_variant, intron_variant Intron 9 of 9 ENST00000252029.8 NP_001944.1 P19971-1E5KRG5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TYMPENST00000252029.8 linkc.1300+1G>A splice_donor_variant, intron_variant Intron 9 of 9 1 NM_001953.5 ENSP00000252029.3 P19971-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
151982
Hom.:
0
Cov.:
34
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
GnomAD4 exome
AF:
0.00000703
AC:
9
AN:
1280838
Hom.:
0
Cov.:
34
AF XY:
0.0000111
AC XY:
7
AN XY:
630272
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
25326
American (AMR)
AF:
0.00
AC:
0
AN:
20598
Ashkenazi Jewish (ASJ)
AF:
0.0000471
AC:
1
AN:
21234
East Asian (EAS)
AF:
0.00
AC:
0
AN:
28036
South Asian (SAS)
AF:
0.00
AC:
0
AN:
66270
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
32192
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
3778
European-Non Finnish (NFE)
AF:
0.00000776
AC:
8
AN:
1030598
Other (OTH)
AF:
0.00
AC:
0
AN:
52806
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.447
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.00000658
AC:
1
AN:
151982
Hom.:
0
Cov.:
34
AF XY:
0.00
AC XY:
0
AN XY:
74244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41410
American (AMR)
AF:
0.00
AC:
0
AN:
15258
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10548
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67962
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
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:
0.00
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

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

Submissions by phenotype

Mitochondrial DNA depletion syndrome 1 Pathogenic:3
Feb 20, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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

- -

Jan 15, 2018
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Mitochondrial neurogastrointestinal encephalomyopathy Pathogenic:1
Jun 25, 2021
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Inborn genetic diseases Pathogenic:1
Mar 28, 2018
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:1
Aug 16, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that disruption of this splice site results in skipping of exon 9, but is expected to preserve the integrity of the reading-frame (PMID: 19056268). ClinVar contains an entry for this variant (Variation ID: 223069). This variant is also known as g.4009G>A. Disruption of this splice site has been observed in individual(s) with mitochondrial neurogastrointestinal encephalomyopathy (PMID: 19056268). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 9 of the TYMP gene. RNA analysis indicates that disruption of this splice site induces altered splicing and likely results in a shortened protein product. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.17
D
BayesDel_noAF
Uncertain
0.010
CADD
Uncertain
26
DANN
Uncertain
0.98
Eigen
Uncertain
0.46
Eigen_PC
Benign
0.12
FATHMM_MKL
Uncertain
0.96
D
PhyloP100
3.2
GERP RS
2.8
PromoterAI
-0.010
Neutral
Mutation Taster
=1/99
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.93
SpliceAI score (max)
0.93
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.93
Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs1064792878; hg19: chr22-50964429; API