2-219279898-C-A

Position:

• chr2-219279898-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_006736.6(DNAJB2):​c.65C>A​(p.Ala22Glu) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.00000547 in 1,461,662 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: DNAJB2 NM_006736.6 missense, splice_region
• Scores: Splicing: ADA: 0.9676
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.12

Genes affected

DNAJB2 (HGNC:5228): (DnaJ heat shock protein family (Hsp40) member B2) This gene is almost exclusively expressed in the brain, mainly in the neuronal layers. It encodes a protein that shows sequence similarity to bacterial DnaJ protein and the yeast homologs. In bacteria, this protein is implicated in protein folding and protein complex dissociation. Alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Jul 2011]

DNAJB2 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.806

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DNAJB2	NM_006736.6	c.65C>A	p.Ala22Glu	missense_variant, splice_region_variant	2/9	ENST00000336576.10	NP_006727.2
DNAJB2	NM_001039550.2	c.65C>A	p.Ala22Glu	missense_variant, splice_region_variant	2/10		NP_001034639.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DNAJB2	ENST00000336576.10	c.65C>A	p.Ala22Glu	missense_variant, splice_region_variant	2/9	1	NM_006736.6	ENSP00000338019.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251022 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135718

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000547 AC: 8 AN: 1461662 Hom.: 0 Cov.: 30 AF XY: 0.00000413 AC XY: 3 AN XY: 727134

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 0.00000630

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neuronopathy, distal hereditary motor, autosomal recessive 5 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 25, 2019

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. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with DNAJB2-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces alanine with glutamic acid at codon 22 of the DNAJB2 protein (p.Ala22Glu). The alanine residue is moderately conserved and there is a moderate physicochemical difference between alanine and glutamic acid. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.30	D
BayesDel_noAF	Pathogenic	0.20
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.44	T;T;.;T;T;.;T
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Uncertain	0.81	D
LIST_S2	Uncertain	0.95	D;D;D;D;D;D;D
M_CAP	Benign	0.083	D
MetaRNN	Pathogenic	0.81	D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.20	T
MutationAssessor	Pathogenic	2.9	M;.;M;.;.;.;.
PrimateAI	Uncertain	0.77	T
PROVEAN	Uncertain	-4.1	D;D;D;D;D;D;D
REVEL	Uncertain	0.63
Sift	Uncertain	0.0010	D;D;D;D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D;D
Polyphen		0.99	D;.;P;.;.;.;.
Vest4		0.94
MutPred		0.75		Loss of MoRF binding (P = 0.0575);Loss of MoRF binding (P = 0.0575);Loss of MoRF binding (P = 0.0575);Loss of MoRF binding (P = 0.0575);Loss of MoRF binding (P = 0.0575);Loss of MoRF binding (P = 0.0575);Loss of MoRF binding (P = 0.0575);
MVP		0.47
MPC		0.88
ClinPred		1.0	D
GERP RS		4.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.98
gMVP		0.83

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.97
dbscSNV1_RF	Pathogenic	0.78
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: rs1357690630; hg19: chr2-220144620;