19-49829855-GC-GCC

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1PM2PP5

The NM_030973.4(MED25):​c.602dupC​(p.Ala202GlyfsTer197) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000273 in 1,612,068 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. P201P) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

MED25
NM_030973.4 frameshift

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:1

Conservation

PhyloP100: 1.57

Publications

3 publications found
Variant links:
Genes affected
MED25 (HGNC:28845): (mediator complex subunit 25) This gene encodes a component of the transcriptional coactivator complex termed the Mediator complex. This complex is required for transcription of most RNA polymerase II-dependent genes. The encoded protein plays a role in chromatin modification and in preinitiation complex assembly. Mutations in this gene are associated with Charcot-Marie-Tooth disease type 2B2. [provided by RefSeq, Apr 2010]
MED25 Gene-Disease associations (from GenCC):
  • congenital cataract-microcephaly-nevus flammeus simplex-severe intellectual disability syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, G2P, Labcorp Genetics (formerly Invitae)
  • autosomal recessive non-syndromic intellectual disability
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Charcot-Marie-Tooth disease type 2B2
    Inheritance: AR Classification: SUPPORTIVE, NO_KNOWN Submitted by: Orphanet, ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 11 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 19-49829855-G-GC is Pathogenic according to our data. Variant chr19-49829855-G-GC is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1348787.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MED25NM_030973.4 linkc.602dupC p.Ala202GlyfsTer197 frameshift_variant Exon 6 of 18 ENST00000312865.10 NP_112235.2 Q71SY5-1
MED25NM_001378355.1 linkc.602dupC p.Ala202GlyfsTer197 frameshift_variant Exon 6 of 18 NP_001365284.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MED25ENST00000312865.10 linkc.602dupC p.Ala202GlyfsTer197 frameshift_variant Exon 6 of 18 1 NM_030973.4 ENSP00000326767.5 Q71SY5-1
MED25ENST00000595185.5 linkc.602dupC p.Ala202GlyfsTer52 frameshift_variant Exon 6 of 7 1 ENSP00000470027.1 M0QYR4
MED25ENST00000538643.5 linkc.181-649dupC intron_variant Intron 2 of 12 1 ENSP00000437496.1 Q71SY5-6
MED25ENST00000593767.3 linkc.602dupC p.Ala202GlyfsTer197 frameshift_variant Exon 6 of 18 3 ENSP00000470692.3 M0QZQ2

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152024
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000725
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000208
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000580
AC:
14
AN:
241254
AF XY:
0.0000683
show subpopulations
Gnomad AFR exome
AF:
0.000133
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000168
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000650
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000267
AC:
39
AN:
1459926
Hom.:
0
Cov.:
33
AF XY:
0.0000358
AC XY:
26
AN XY:
726274
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33462
American (AMR)
AF:
0.00
AC:
0
AN:
44516
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26098
East Asian (EAS)
AF:
0.0000756
AC:
3
AN:
39668
South Asian (SAS)
AF:
0.0000812
AC:
7
AN:
86180
European-Finnish (FIN)
AF:
0.000114
AC:
6
AN:
52484
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.0000180
AC:
20
AN:
1111436
Other (OTH)
AF:
0.0000332
AC:
2
AN:
60320
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.446
Heterozygous variant carriers
0
2
4
7
9
11
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:
0.0000329
AC:
5
AN:
152142
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74376
show subpopulations
African (AFR)
AF:
0.0000723
AC:
3
AN:
41518
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5172
South Asian (SAS)
AF:
0.000208
AC:
1
AN:
4806
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10598
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67984
Other (OTH)
AF:
0.00
AC:
0
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.535
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:
0.0000868
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

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

Submissions by phenotype

Charcot-Marie-Tooth disease type 2B2;C4225323:Congenital cataract-microcephaly-nevus flammeus simplex-severe intellectual disability syndrome Pathogenic:1
Nov 03, 2022
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

- -

Charcot-Marie-Tooth disease type 2 Uncertain:1
Oct 16, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Ala202Glyfs*197) in the MED25 gene. It is expected to result in an absent or disrupted protein product. However, the current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in MED25 cause disease. This variant is present in population databases (rs748546983, ExAC 0.07%). This variant has not been reported in the literature in individuals with MED25-related conditions. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
1.6
Mutation Taster
=18/182
disease causing

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: rs748546983; hg19: chr19-50333112; COSMIC: COSV57204133; COSMIC: COSV57204133; API