2-151679935-C-CATT

Position:

• chr2-151679935-C-CATT

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PM4_Supporting PP5

The NM_001164507.2(NEB):​c.3129_3130insAAT​(p.Asn1043dup) variant causes a inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000548 in 1,460,922 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: NEB NM_001164507.2 inframe_insertion
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:2
• Conservation: PhyloP100: 1.05

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 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_001164507.2. Strenght limited to Supporting due to length of the change: 1aa.
• PP5: Variant 2-151679935-C-CATT is Pathogenic according to our data. Variant chr2-151679935-C-CATT is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 534006.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
NEB	NM_001164507.2	c.3129_3130insAAT	p.Asn1043dup	inframe_insertion	31/182	ENST00000427231.7	NP_001157979.2
NEB	NM_001164508.2	c.3129_3130insAAT	p.Asn1043dup	inframe_insertion	31/182	ENST00000397345.8	NP_001157980.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
NEB	ENST00000397345.8	c.3129_3130insAAT	p.Asn1043dup	inframe_insertion	31/182	5	NM_001164508.2	ENSP00000380505	P5
NEB	ENST00000427231.7	c.3129_3130insAAT	p.Asn1043dup	inframe_insertion	31/182	5	NM_001164507.2	ENSP00000416578	A2
NEB	ENST00000409198.5	c.3129_3130insAAT	p.Asn1043dup	inframe_insertion	31/150	5		ENSP00000386259

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000803 AC: 2 AN: 249178 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135178

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000290

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: 0.000165

GnomAD4 exome AF: 0.00000548 AC: 8 AN: 1460922 Hom.: 0 Cov.: 32 AF XY: 0.00000550 AC XY: 4 AN XY: 726804

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000894

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: 0.00000270

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 31

Bravo AF: 0.00000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Nemaline myopathy 2 Pathogenic:1 Uncertain:1

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Nov 11, 2019	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Sep 27, 2023	This variant is present in population databases (no rsID available, gnomAD 0.006%). This variant, c.3127_3129dup, results in the insertion of 1 amino acid(s) of the NEB protein (p.Asn1043dup), but otherwise preserves the integrity of the reading frame. This variant has been observed in individual(s) with nemaline myopathy (Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 534006). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Nemaline myopathy 2;C5543431:Arthrogryposis multiplex congenita 6 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Apr 18, 2022

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1288870299; hg19: chr2-152536449;