2-151600441-C-G

Variant names:

• chr2-151600441-C-G
• rs1553862061
• NM_001164507.2:c.13788+1G>C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PVS1_Moderate PP5_Moderate

The NM_001164507.2(NEB):​c.13788+1G>C variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 0)
• Consequence: NEB NM_001164507.2 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.71
• Publications: 0 publications found

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]

NEB Gene-Disease associations (from GenCC):

• nemaline myopathy 2

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, LIMITED Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, G2P, Ambry Genetics
• childhood-onset nemaline myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• intermediate nemaline myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• typical nemaline myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• lethal multiple pterygium syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• severe congenital nemaline myopathy

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.0121979825 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PP5: Variant 2-151600441-C-G is Pathogenic according to our data. Variant chr2-151600441-C-G is described in ClinVar as Pathogenic. ClinVar VariationId is 935753.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NEB	NM_001164507.2	c.13788+1G>C		splice_donor_variant, intron_variant	Intron 89 of 181	ENST00000427231.7	NP_001157979.2
NEB	NM_001164508.2	c.13788+1G>C		splice_donor_variant, intron_variant	Intron 89 of 181	ENST00000397345.8	NP_001157980.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NEB	ENST00000397345.8	c.13788+1G>C		splice_donor_variant, intron_variant	Intron 89 of 181	5	NM_001164508.2	ENSP00000380505.3
NEB	ENST00000427231.7	c.13788+1G>C		splice_donor_variant, intron_variant	Intron 89 of 181	5	NM_001164507.2	ENSP00000416578.2
NEB	ENST00000409198.5	c.11601+9368G>C		intron_variant	Intron 78 of 149	5		ENSP00000386259.1

Frequencies

GnomAD3 genomes Cov.: 0

GnomAD4 exome Cov.: 0

GnomAD4 genome Cov.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Nemaline myopathy 2 Pathogenic:1

Jan 27, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant occurs in a region of NEB (Exons 82-105) consisting of three highly homologous 8-exon repeat units (exons 82-89, exons 90-97, exons 98-105). Sequence variants in this region can be detected, but this assay cannot determine which of the three repeat units is affected, and zygosity is often ambiguous. All variants in this region are reported relative to the exon 82-89 repeat. This sequence change affects a donor splice site in intron 89 of the NEB gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in NEB are known to be pathogenic (PMID: 25205138). The frequency data for this variant in the population databases (gnomAD) is considered unreliable due to the presence of homologous sequence, such as pseudogenes or paralogs, in the genome. Disruption of this splice site has been observed in individuals with clinical features of congenital myopathy (PMID: 25205138; Invitae). ClinVar contains an entry for this variant (Variation ID: 935753). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	-0.030
CADD	Pathogenic	32
DANN	Benign	0.96
Eigen	Pathogenic	0.73
Eigen_PC	Uncertain	0.46
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		7.7
GERP RS		2.5
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.99		Position offset: 1

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

Other links and lift over

dbSNP: rs1553862061; hg19: chr2-152456955;