NM_030973.4:c.1677G>A

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_030973.4(MED25):​c.1677G>A​(p.Met559Ile) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000514 in 1,557,392 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely benign in ClinVar.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000050 ( 0 hom. )

Consequence

MED25
NM_030973.4 missense, splice_region

Scores

4
15

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 1.93

Publications

1 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: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MED25NM_030973.4 linkc.1677G>A p.Met559Ile missense_variant, splice_region_variant Exon 15 of 18 ENST00000312865.10 NP_112235.2
MED25NM_001378355.1 linkc.1677G>A p.Met559Ile missense_variant, splice_region_variant Exon 15 of 18 NP_001365284.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MED25ENST00000312865.10 linkc.1677G>A p.Met559Ile missense_variant, splice_region_variant Exon 15 of 18 1 NM_030973.4 ENSP00000326767.5

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152186
Hom.:
0
Cov.:
32
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:
0.00
Gnomad OTH
AF:
0.000478
GnomAD2 exomes
AF:
0.00000592
AC:
1
AN:
168864
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000377
Gnomad ASJ exome
AF:
0.00
Gnomad EAS 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:
0.00000498
AC:
7
AN:
1405206
Hom.:
0
Cov.:
33
AF XY:
0.00000576
AC XY:
4
AN XY:
694028
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
31974
American (AMR)
AF:
0.0000266
AC:
1
AN:
37528
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
24922
East Asian (EAS)
AF:
0.00
AC:
0
AN:
36694
South Asian (SAS)
AF:
0.00
AC:
0
AN:
79602
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
48826
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4344
European-Non Finnish (NFE)
AF:
0.00000554
AC:
6
AN:
1083334
Other (OTH)
AF:
0.00
AC:
0
AN:
57982
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.461
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

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:
0.00000657
AC:
1
AN:
152186
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74334
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68030
Other (OTH)
AF:
0.000478
AC:
1
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
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: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Charcot-Marie-Tooth disease type 2 Uncertain:1
Jul 19, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 559 of the MED25 protein (p.Met559Ile). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with MED25-related conditions. ClinVar contains an entry for this variant (Variation ID: 476801). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The isoleucine 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 create or strengthen a splice site. 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
AlphaMissense
Benign
0.17
BayesDel_addAF
Benign
-0.089
T
BayesDel_noAF
Benign
-0.25
CADD
Uncertain
25
DANN
Benign
0.95
DEOGEN2
Benign
0.085
.;T;.;.;.
Eigen
Benign
-0.28
Eigen_PC
Benign
-0.17
FATHMM_MKL
Uncertain
0.83
D
LIST_S2
Benign
0.72
T;T;T;.;.
M_CAP
Uncertain
0.24
D
MetaRNN
Benign
0.20
T;T;T;T;T
MetaSVM
Benign
-0.75
T
MutationAssessor
Benign
1.5
.;L;.;.;.
PhyloP100
1.9
PrimateAI
Uncertain
0.64
T
PROVEAN
Benign
-0.81
.;N;N;.;.
REVEL
Benign
0.20
Sift
Uncertain
0.023
.;D;D;.;.
Sift4G
Benign
0.31
T;T;T;T;.
Polyphen
0.0010
.;B;.;.;.
Vest4
0.31
MutPred
0.43
.;Gain of loop (P = 0.0166);.;.;.;
MVP
0.65
MPC
0.20
ClinPred
0.21
T
GERP RS
2.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.11
gMVP
0.25
Mutation Taster
=87/13
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.35
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.35
Position offset: 2

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

Publications

Other links and lift over

dbSNP: rs369006637; hg19: chr19-50338793; API