2-148469270-G-C

Variant names:

• chr2-148469270-G-C
• rs137977565
• NM_001378120.1:c.1327G>C

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_001378120.1(MBD5):​c.1327G>C​(p.Val443Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,682 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. 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: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MBD5 NM_001378120.1 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.44
• Publications: 0 publications found

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

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.38812044).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MBD5	NM_001378120.1	c.1327G>C	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
MBD5	ENST00000642680.2	c.1327G>C	p.Val443Leu	missense_variant	Exon 8 of 14		NM_001378120.1	ENSP00000493871.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461682 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727128

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: 0.0000116 AC: 1 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: 0.00 AC: 0 AN: 1111918

Other (OTH) AF: 0.00 AC: 0 AN: 60390

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

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	0.39	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		0.91	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

Other links and lift over

dbSNP: rs137977565; hg19: chr2-149226839;