1-156135913-G-T

Position:

• chr1-156135913-G-T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_170707.4(LMNA):​c.949G>T​(p.Glu317*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,384 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Synonymous variant affecting the same amino acid position (i.e. E317E) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: LMNA NM_170707.4 stop_gained
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 8.12

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]

LMNA (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 11 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 1-156135913-G-T is Pathogenic according to our data. Variant chr1-156135913-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 235004.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LMNA	NM_170707.4	c.949G>T	p.Glu317*	stop_gained	6/12	ENST00000368300.9	NP_733821.1
LMNA	NM_005572.4	c.949G>T	p.Glu317*	stop_gained	6/10	ENST00000677389.1	NP_005563.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LMNA	ENST00000368300.9	c.949G>T	p.Glu317*	stop_gained	6/12	1	NM_170707.4	ENSP00000357283.4
LMNA	ENST00000677389.1	c.949G>T	p.Glu317*	stop_gained	6/10		NM_005572.4	ENSP00000503633.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461384 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 726994

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Stanford Center for Inherited Cardiovascular Disease, Stanford University

Jun 14, 2013

Note this variant was found in clinical genetic testing performed by one or more labs who may also submit to ClinVar. Thus any internal case data may overlap with the internal case data of other labs. The interpretation reviewed below is that of the Stanford Center for Inherited Cardiovascular Disease. LMNA p.Glu317Ter This variant is novel, it has not been reported in peer reviewed literature to date. This nucleotide substitution is expected to create a premature stop codon and a truncated Lamin A/C protein. There are at least 10 different nonsense variants reported in the LMNA gene associated with various phenotypes, primarily dilated cardiomyopathy, conduction system disease, or muscular dystrophy (LGMD, EDMD) (Cowan J et al 2011, http://www.dmd.nl/lmna_seqvar.html). Geiger et al (2007) report a nearby nonsense variant (R321X) in a family with DCM and sudden death; three affected family members were genotyped and they all had the variant. mRNA and protein studies on patient skin fibroblasts and LV myocardium were consistent with mRNA mediated nonsense decay. Van Engelen et al (2005) reported another nonsense variant, p.Tyr259Ter segregating with limb-girdle muscular dystrophy in nine affected family members. A homozygous baby born to consanguineous heterozygous parents died at birth because of severe generalized muscular dystrophy. The variant is not listed in dbSNP or 1000 genomes (as of September 2011). No nonsense variants were identified in 47 healthy elderly individuals studied by Halaschek-Wiener et al (2009). This variant was not present in the NHLBI exome sequencing project data on LMNA, which includes variant calls on ~6500 individuals of European and African American descent (and, of note, there are currently no frameshift or nonsense variants in control individuals in this dataset, as of 6/14/2013). LMNA variants are frequently associated with dilated cardiomyopathy and conduction system disease. Patients with Emery-Dreifuss muscular dystrophy associated with LMNA variants have been reported with either dilated cardiomyopathy or a restrictive cardiomyopathy (Raffaele di Barletta et al 2000, Sanna et al 2003). However, we have not been able to find any cases of isolated restrictive cardiomyopathy due to LMNA variants. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.60	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	45
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	0.99	D
Vest4		0.96
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8

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: rs56816490; hg19: chr1-156105704;