1-156136312-G-T

Variant names:

• chr1-156136312-G-T
• NM_170707.4:c.1256G>T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PM5 PP2 PP3

The NM_170707.4(LMNA):​c.1256G>T​(p.Arg419Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000343 in 1,459,852 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R419C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: LMNA NM_170707.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:1
• Conservation: PhyloP100: 8.02

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 Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-156136311-C-T is described in Lovd as [Likely_pathogenic].
• PP2: Missense variant in the LMNA gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 178 curated pathogenic missense variants (we use a threshold of 10). The gene has 69 curated benign missense variants. Gene score misZ: 2.3673 (below the threshold of 3.09). Trascript score misZ: 3.0905 (above the threshold of 3.09). GenCC associations: The gene is linked to familial partial lipodystrophy, Dunnigan type, autosomal recessive Emery-Dreifuss muscular dystrophy, LMNA-related cardiocutaneous progeria syndrome, atrioventricular block, dilated cardiomyopathy 1A, Emery-Dreifuss muscular dystrophy 2, autosomal dominant, atypical Werner syndrome, restrictive dermopathy 1, autosomal semi-dominant severe lipodystrophic laminopathy, Emery-Dreifuss muscular dystrophy 3, autosomal recessive, dilated cardiomyopathy, Charcot-Marie-Tooth disease type 2B1, dilated cardiomyopathy-hypergonadotropic hypogonadism syndrome, arrhythmogenic right ventricular cardiomyopathy, familial isolated dilated cardiomyopathy, mandibuloacral dysplasia with type A lipodystrophy, autosomal dominant Emery-Dreifuss muscular dystrophy, heart-hand syndrome, Slovenian type, congenital muscular dystrophy due to LMNA mutation, lethal restrictive dermopathy, Hutchinson-Gilford progeria syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.816

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
LMNA	NM_170707.4	c.1256G>T	p.Arg419Leu	missense_variant	Exon 7 of 12	ENST00000368300.9	NP_733821.1
LMNA	NM_005572.4	c.1256G>T	p.Arg419Leu	missense_variant	Exon 7 of 10	ENST00000677389.1	NP_005563.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
LMNA	ENST00000368300.9	c.1256G>T	p.Arg419Leu	missense_variant	Exon 7 of 12	1	NM_170707.4	ENSP00000357283.4
LMNA	ENST00000677389.1	c.1256G>T	p.Arg419Leu	missense_variant	Exon 7 of 10		NM_005572.4	ENSP00000503633.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1459852 Hom.: 0 Cov.: 34 AF XY: 0.00000413 AC XY: 3 AN XY: 726260

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: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Primary dilated cardiomyopathy Uncertain:1

Dec 18, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces arginine with leucine at codon 419 of the LMNA protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with LMNA-related disorders in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.86
CardioboostCm	Benign	0.067
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.83	.;.;.;D;.;.;.;.;T
Eigen	Uncertain	0.48
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.60	D
MetaRNN	Pathogenic	0.82	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.1	M;.;M;M;M;.;.;.;.
PrimateAI	Uncertain	0.62	T
PROVEAN	Uncertain	-3.0	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.77
Sift	Benign	0.046	D;D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.049	D;D;D;D;D;T;T;T;D
Polyphen		1.0	D;.;P;D;.;.;D;.;.
Vest4		0.63
MutPred		0.42		Gain of ubiquitination at K418 (P = 0.0354);Gain of ubiquitination at K418 (P = 0.0354);Gain of ubiquitination at K418 (P = 0.0354);Gain of ubiquitination at K418 (P = 0.0354);Gain of ubiquitination at K418 (P = 0.0354);.;.;.;.;
MVP		0.99
MPC		0.47
ClinPred		0.95	D
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.9
Varity_R		0.28
gMVP		0.93

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-156106103;