2-151549718-C-T

Position:

• chr2-151549718-C-T

Variant summary

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

The NM_001164508.2(NEB):​c.19967G>A​(p.Arg6656His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000157 in 1,590,358 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000016 (0 hom.)
• Consequence: NEB NM_001164508.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.705

Genes affected

NEB (HGNC:7720): (nebulin) This gene encodes nebulin, a giant protein component of the cytoskeletal matrix that coexists with the thick and thin filaments within the sarcomeres of skeletal muscle. In most vertebrates, nebulin accounts for 3 to 4% of the total myofibrillar protein. The encoded protein contains approximately 30-amino acid long modules that can be classified into 7 types and other repeated modules. Protein isoform sizes vary from 600 to 800 kD due to alternative splicing that is tissue-, species-,and developmental stage-specific. Of the 183 exons in the nebulin gene, at least 43 are alternatively spliced, although exons 143 and 144 are not found in the same transcript. Of the several thousand transcript variants predicted for nebulin, the RefSeq Project has decided to create three representative RefSeq records. Mutations in this gene are associated with recessive nemaline myopathy. [provided by RefSeq, Sep 2009]

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=0.0942238).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NEB	NM_001164507.2	c.19967G>A	p.Arg6656His	missense_variant	130/182	ENST00000427231.7	NP_001157979.2
NEB	NM_001164508.2	c.19967G>A	p.Arg6656His	missense_variant	130/182	ENST00000397345.8	NP_001157980.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NEB	ENST00000397345.8	c.19967G>A	p.Arg6656His	missense_variant	130/182	5	NM_001164508.2	ENSP00000380505.3
NEB	ENST00000427231.7	c.19967G>A	p.Arg6656His	missense_variant	130/182	5	NM_001164507.2	ENSP00000416578.2

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 152050 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000160 AC: 23 AN: 1438190 Hom.: 0 Cov.: 30 AF XY: 0.0000182 AC XY: 13 AN XY: 712768

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000242

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000486

Gnomad4 FIN exome AF: 0.0000384

Gnomad4 NFE exome AF: 0.0000127

Gnomad4 OTH exome AF: 0.0000336

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152168 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74378

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000655

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000329 Hom.: 0

Bravo AF: 0.00000756

ExAC AF: 0.0000249 AC: 3

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Nemaline myopathy 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 27, 2022

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 6656 of the NEB protein (p.Arg6656His). 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 NEB-related conditions. ClinVar contains an entry for this variant (Variation ID: 950354). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0". The histidine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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	0.073
BayesDel_addAF	Benign	-0.20	T
BayesDel_noAF	Benign	-0.52
CADD	Benign	19
DANN	Uncertain	0.99
DEOGEN2	Benign	0.022	.;.;T;.;T;T;.;.
Eigen	Benign	-0.19
Eigen_PC	Benign	-0.086
FATHMM_MKL	Benign	0.092	N
LIST_S2	Uncertain	0.88	D;D;T;D;D;D;.;.
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.094	T;T;T;T;T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.0	N;.;.;.;N;.;.;.
PrimateAI	Benign	0.26	T
PROVEAN	Benign	-2.1	N;N;.;N;N;N;.;.
REVEL	Benign	0.084
Sift	Benign	0.12	T;T;.;T;T;T;.;.
Sift4G	Benign	0.28	T;T;T;T;T;T;T;T
Polyphen		0.0010	.;.;.;.;B;.;.;.
Vest4		0.094
MVP		0.35
MPC		0.063
ClinPred		0.30	T
GERP RS		4.3
Varity_R		0.073
gMVP		0.10

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: rs767200761; hg19: chr2-152406232;