3-129431523-T-C

Position:

• chr3-129431523-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001276270.2(MBD4):​c.1703A>G​(p.His568Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,096 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 (★). Synonymous variant affecting the same amino acid position (i.e. H568H) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MBD4 NM_001276270.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.79

Genes affected

MBD4 (HGNC:6919): (methyl-CpG binding domain 4, DNA glycosylase) The protein encoded by this gene is a member of a family of nuclear proteins related by the presence of a methyl-CpG binding domain (MBD). These proteins are capable of binding specifically to methylated DNA, and some members can also repress transcription from methylated gene promoters. This protein contains an MBD domain at the N-terminus that functions both in binding to methylated DNA and in protein interactions and a C-terminal mismatch-specific glycosylase domain that is involved in DNA repair. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Jan 2013]

IFT122 (HGNC:13556): (intraflagellar transport 122) This gene encodes a member of the WD repeat protein family. WD repeats are minimally conserved regions of approximately 40 amino acids typically bracketed by gly-his and trp-asp (GH-WD), which may facilitate formation of heterotrimeric or multiprotein complexes. Members of this family are involved in a variety of cellular processes, including cell cycle progression, signal transduction, apoptosis, and gene regulation. This cytoplasmic protein contains seven WD repeats and an AF-2 domain which function by recruiting coregulatory molecules and in transcriptional activation. Mutations in this gene cause cranioectodermal dysplasia-1. A related pseudogene is located on chromosome 3. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jul 2013]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.14429724).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MBD4	NM_001276270.2	c.1703A>G	p.His568Arg	missense_variant	8/8	ENST00000429544.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MBD4	ENST00000429544.7	c.1703A>G	p.His568Arg	missense_variant	8/8	1	NM_001276270.2	A2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251160 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135744

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS 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: 0.00000137 AC: 2 AN: 1461096 Hom.: 0 Cov.: 29 AF XY: 0.00000275 AC XY: 2 AN XY: 726876

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000447

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 03, 2023

This sequence change replaces histidine, which is basic and polar, with arginine, which is basic and polar, at codon 574 of the MBD4 protein (p.His574Arg). This variant is present in population databases (rs370417942, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with MBD4-related conditions. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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	0.12
BayesDel_addAF	Benign	-0.15	T
BayesDel_noAF	Benign	-0.36
CADD	Benign	22
DANN	Uncertain	0.98
DEOGEN2	Benign	0.42	.;T;.
Eigen	Benign	0.0075
Eigen_PC	Benign	0.16
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Benign	0.76	T;T;T
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.14	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.1	.;L;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.60	T
PROVEAN	Uncertain	-3.5	D;D;D
REVEL	Benign	0.080
Sift	Uncertain	0.023	D;D;T
Sift4G	Benign	0.17	T;T;T
Polyphen		0.031	B;B;.
Vest4		0.093
MutPred		0.19		.;Loss of ubiquitination at K576 (P = 0.059);.;
MVP		0.42
MPC		0.48
ClinPred		0.89	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.63
gMVP		0.72

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

LitVar

Other links and lift over

dbSNP: rs370417942; hg19: chr3-129150366; COSMIC: COSV51445765; COSMIC: COSV51445765;