NM_001378120.1:c.1327G>T

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4BS1_SupportingBS2

The NM_001378120.1(MBD5):​c.1327G>T​(p.Val443Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000266 in 1,613,656 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 variant affecting the same amino acid position, but resulting in a different missense (i.e. V443M) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000026 ( 0 hom. )

Consequence

MBD5
NM_001378120.1 missense

Scores

4
4
11

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 9.44

Publications

2 publications found
Variant links:
Genes affected
MBD5 (HGNC:20444): (methyl-CpG binding domain protein 5) This gene encodes a member of the methyl-CpG-binding domain (MBD) family. The MBD consists of about 70 residues and is the minimal region required for a methyl-CpG-binding protein binding specifically to methylated DNA. In addition to the MBD domain, this protein contains a PWWP domain (Pro-Trp-Trp-Pro motif), which consists of 100-150 amino acids and is found in numerous proteins that are involved in cell division, growth and differentiation. Mutations in this gene cause an autosomal dominant type of cognitive disability. The encoded protein interacts with the polycomb repressive complex PR-DUB which catalyzes the deubiquitination of a lysine residue of histone 2A. Haploinsufficiency of this gene is associated with a syndrome involving microcephaly, intellectual disabilities, severe speech impairment, and seizures. Alternatively spliced transcript variants have been found, but their full-length nature is not determined. [provided by RefSeq, Jul 2017]
MBD5 Gene-Disease associations (from GenCC):
  • complex neurodevelopmental disorder
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • intellectual disability, autosomal dominant 1
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • autosomal dominant non-syndromic intellectual disability
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.3562655).
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.0000329 (5/151974) while in subpopulation NFE AF = 0.0000735 (5/68000). AF 95% confidence interval is 0.0000285. There are 0 homozygotes in GnomAd4. There are 4 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAd4 at 5 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MBD5NM_001378120.1 linkc.1327G>T p.Val443Leu missense_variant Exon 8 of 14 ENST00000642680.2 NP_001365049.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MBD5ENST00000642680.2 linkc.1327G>T p.Val443Leu missense_variant Exon 8 of 14 NM_001378120.1 ENSP00000493871.2 A0A2R8YDL9

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
151974
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000400
AC:
1
AN:
250002
AF XY:
0.00000740
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000888
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000260
AC:
38
AN:
1461682
Hom.:
0
Cov.:
33
AF XY:
0.0000206
AC XY:
15
AN XY:
727128
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44692
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39666
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53396
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000333
AC:
37
AN:
1111918
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.489
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:
151974
Hom.:
0
Cov.:
32
AF XY:
0.0000539
AC XY:
4
AN XY:
74202
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41378
American (AMR)
AF:
0.00
AC:
0
AN:
15246
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:
4806
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10578
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68000
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.505
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

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:
0.00
Hom.:
0
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Intellectual disability, autosomal dominant 1 Uncertain:2
Sep 03, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 443 of the MBD5 protein (p.Val443Leu). This variant is present in population databases (rs137977565, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with MBD5-related conditions. ClinVar contains an entry for this variant (Variation ID: 421660). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt MBD5 protein function with a negative predictive value of 80%. 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. -

-
UNC Molecular Genetics Laboratory, University of North Carolina at Chapel Hill
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:research

The MBD5 c.1327G>T p.V443L missense variant has not previously been reported in any patients with autosomal dominant intellectual disability and is considered a variant of uncertain significance. -

not provided Uncertain:1
Feb 20, 2017
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The V443L variant in the MBD5 gene has not been reported previously as a pathogenic variant, nor as a benign variant, to our knowledge. The V443L variant was not observed in approximately 6500 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 V443L variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. In addition, this substitution occurs at a position that is conserved across species. However, in silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. We therefore interpret V443L as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.31
BayesDel_addAF
Uncertain
0.099
D
BayesDel_noAF
Benign
-0.10
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Benign
0.074
T;.;.;.;T
Eigen
Pathogenic
0.69
Eigen_PC
Pathogenic
0.73
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
D;.;D;D;D
M_CAP
Benign
0.016
T
MetaRNN
Benign
0.36
T;T;T;T;T
MetaSVM
Benign
-0.59
T
MutationAssessor
Benign
0.97
L;.;.;L;.
PhyloP100
9.4
PrimateAI
Uncertain
0.74
T
PROVEAN
Benign
-0.82
N;.;.;.;N
REVEL
Benign
0.21
Sift
Pathogenic
0.0
D;.;.;.;D
Sift4G
Benign
0.15
T;.;.;T;T
Polyphen
0.99
D;.;.;.;.
Vest4
0.58
MutPred
0.22
Loss of sheet (P = 0.0228);Loss of sheet (P = 0.0228);Loss of sheet (P = 0.0228);Loss of sheet (P = 0.0228);Loss of sheet (P = 0.0228);
MVP
0.34
MPC
0.28
ClinPred
0.81
D
GERP RS
5.2
Varity_R
0.58
gMVP
0.37
Mutation Taster
=77/23
polymorphism

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: rs137977565; hg19: chr2-149226839; COSMIC: COSV68696144; COSMIC: COSV68696144; API