1-156136021-C-T

Variant names:

• chr1-156136021-C-T
• rs267607623
• NM_170707.4:c.1057C>T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_170707.4(LMNA):​c.1057C>T​(p.Gln353*) variant causes a stop gained change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: LMNA NM_170707.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4 U:1
• Conservation: PhyloP100: 6.08

Genes affected

LMNA (HGNC:6636): (lamin A/C) The protein encoded by this gene is part of the nuclear lamina, a two-dimensional matrix of proteins located next to the inner nuclear membrane. The lamin family of proteins make up the matrix and are highly conserved in evolution. During mitosis, the lamina matrix is reversibly disassembled as the lamin proteins are phosphorylated. Lamin proteins are thought to be involved in nuclear stability, chromatin structure and gene expression. Vertebrate lamins consist of two types, A and B. Alternative splicing results in multiple transcript variants. Mutations in this gene lead to several diseases: Emery-Dreifuss muscular dystrophy, familial partial lipodystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy, Charcot-Marie-Tooth disease, and Hutchinson-Gilford progeria syndrome. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-156136021-C-T is Pathogenic according to our data. Variant chr1-156136021-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 200939.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LMNA	NM_170707.4	c.1057C>T	p.Gln353*	stop_gained	Exon 6 of 12	ENST00000368300.9	NP_733821.1
LMNA	NM_005572.4	c.1057C>T	p.Gln353*	stop_gained	Exon 6 of 10	ENST00000677389.1	NP_005563.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LMNA	ENST00000368300.9	c.1057C>T	p.Gln353*	stop_gained	Exon 6 of 12	1	NM_170707.4	ENSP00000357283.4
LMNA	ENST00000677389.1	c.1057C>T	p.Gln353*	stop_gained	Exon 6 of 10		NM_005572.4	ENSP00000503633.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251314 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135882

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

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: 0.00

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4 Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Sep 25, 2019

Mayo Clinic Laboratories, Mayo Clinic

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PVS1, PM1, PM2 -

Nov 27, 2023

GeneDx

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 28152038, 29861492, 25886484) -

Charcot-Marie-Tooth disease type 2 Pathogenic:1

Jan 29, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Gln353*) in the LMNA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in LMNA are known to be pathogenic (PMID: 18585512, 18926329). This variant is present in population databases (rs267607623, gnomAD 0.003%). This premature translational stop signal has been observed in individual(s) with amyotrophy of the lower limbs, arrhythmia and cardiac hypofunction (PMID: 25886484). ClinVar contains an entry for this variant (Variation ID: 200939). For these reasons, this variant has been classified as Pathogenic. -

Cardiovascular phenotype Pathogenic:1

Apr 11, 2018

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Q353* pathogenic mutation (also known as c.1057C>T), located in coding exon 6 of the LMNA gene, results from a C to T substitution at nucleotide position 1057. This changes the amino acid from a glutamine to a stop codon within coding exon 6. This mutation has been previously reported in a patient with an LMNA-associated laminopathy (Iwahara N et al. BMC Neurol. 2015;15:13). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Neuronopathy, distal hereditary motor, autosomal dominant Uncertain:1

-

Inherited Neuropathy Consortium

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	42
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.97	D
Vest4		0.97
GERP RS		5.7
RBP_binding_hub_radar		0.92
RBP_regulation_power_radar		3.8

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: rs267607623; hg19: chr1-156105812;