rs59601651

Positions:

• chr1-156138537-C-G
• chr1-156138537-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PM5 PP2

The NM_170707.4(LMNA):​c.1748C>G​(p.Ser583Trp) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. 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. S583L) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: LMNA NM_170707.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 4.82

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 7 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_170707.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr1-156138537-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 66864.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Uncertain_significance=6, not_provided=1, Likely_pathogenic=2}.
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), LMNA. . Gene score misZ: 2.3673 (greater than the threshold 3.09). Trascript score misZ: 3.0905 (greater than threshold 3.09). The gene has 178 curated pathogenic missense variants (we use a threshold of 10). The gene has 69 curated benign missense variants. GenCC has associacion of the gene with 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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LMNA	NM_170707.4	c.1748C>G	p.Ser583Trp	missense_variant	11/12	ENST00000368300.9	NP_733821.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LMNA	ENST00000368300.9	c.1748C>G	p.Ser583Trp	missense_variant	11/12	1	NM_170707.4	ENSP00000357283.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jan 28, 2014

The Ser583Trp variant in LMNA has not been reported in individuals with cardiomy opathy. Data from large population studies is insufficient to assess its freque ncy in the general population. Computational analyses (biochemical amino acid pr operties, conservation, PolyPhen2, and SIFT) suggest that this variant may impac t the protein, though this information is not predictive enough to determine pat hogenicity. Another variant at the same position (Ser583Leu) has been reported i n 3 individuals with familial partial lipodystrophy and segregated in 5 affected relatives (Savage 2004), which supports that a change at this position is not t olerated. In summary, the available data is so far consistent with a pathogenic role but additional studies are needed to fully assess the clinical significanc e of this variant. -

Charcot-Marie-Tooth disease type 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 03, 2022

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C15"). ClinVar contains an entry for this variant (Variation ID: 178933). This variant has not been reported in the literature in individuals affected with LMNA-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces serine, which is neutral and polar, with tryptophan, which is neutral and slightly polar, at codon 583 of the LMNA protein (p.Ser583Trp). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
CardioboostCm	Uncertain	0.14
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.26
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.71	.;D;.;.;.;T
Eigen	Uncertain	0.59
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Uncertain	0.79	D
LIST_S2	Uncertain	0.97	D;D;D;D;D;D
M_CAP	Pathogenic	0.56	D
MetaRNN	Uncertain	0.67	D;D;D;D;D;D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Uncertain	2.1	.;M;M;.;.;.
PrimateAI	Pathogenic	0.81	D
PROVEAN	Uncertain	-3.2	D;N;N;N;N;D
REVEL	Uncertain	0.58
Sift	Pathogenic	0.0	D;D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D
Polyphen		1.0	D;D;.;.;.;.
Vest4		0.72
MutPred		0.33		.;Loss of disorder (P = 0.0022);Loss of disorder (P = 0.0022);.;.;.;
MVP		0.89
MPC		1.3
ClinPred		0.99	D
GERP RS		5.0
Varity_R		0.46
gMVP		0.96

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: rs59601651; hg19: chr1-156108328;