rs59270054

Positions:

• chr1-156115162-G-A
• chr1-156115162-G-C

Variant summary

Our verdict is Pathogenic. Variant got 17 ACMG points: 17P and 0B. PM1 PM2 PM5 PP2 PP3_Moderate PP5_Very_Strong

The NM_170707.4(LMNA):​c.244G>A​(p.Glu82Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E82Q) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: LMNA NM_170707.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3 O:1
• Conservation: PhyloP100: 10.0

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 17 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 13 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 chr1-156115163-A-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2089379.Status of the report is criteria_provided_single_submitter, 1 stars.
• 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). GenCC has associacion of 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.934
• PP5: Variant 1-156115162-G-A is Pathogenic according to our data. Variant chr1-156115162-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 66882.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-156115162-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LMNA	NM_170707.4	c.244G>A	p.Glu82Lys	missense_variant	1/12	ENST00000368300.9	NP_733821.1
LMNA	NM_005572.4	c.244G>A	p.Glu82Lys	missense_variant	1/10	ENST00000677389.1	NP_005563.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LMNA	ENST00000368300.9	c.244G>A	p.Glu82Lys	missense_variant	1/12	1	NM_170707.4	ENSP00000357283.4
LMNA	ENST00000677389.1	c.244G>A	p.Glu82Lys	missense_variant	1/10		NM_005572.4	ENSP00000503633.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1 Other:1

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Mar 30, 2015	The E82K mutation was reported to segregate with DCM and atrial ventricular block in eight individuals from two Chinese families (Wang et al., 2006; Wu et al., 2010). E82K was not observed in approximately 6500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. In vitro studies showed E82K significantly reduced expression and altered localization of connexin 43 (Sun et al., 2010). Studies in transgenic mice showed E82K activates the FAS and mitochondrial pathways of apoptosis in heart tissue (Lu et al., 2010). E82K is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved across species. In silico analysis predicts this variant is probably damaging to the protein structure/function. Missense mutations in nearby residues (R72L, R72C, L85R, R89L) have been reported in the Human Gene Mutation Database in association with cardiomyopathy (Stenson et al., 2014), supporting the functional importance of this region of the protein. -
not provided, no classification provided	literature only	Epithelial Biology; Institute of Medical Biology, Singapore	-	- -

Charcot-Marie-Tooth disease type 2 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 27, 2023

For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects LMNA function (PMID: 20497714, 21151901). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt LMNA protein function. ClinVar contains an entry for this variant (Variation ID: 66882). This missense change has been observed in individual(s) with dilated cardiomyopathy (DCM) and atrioventricular (AV) block (PMID: 16630578, 20155465). It has also been observed to segregate with disease in related individuals. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 82 of the LMNA protein (p.Glu82Lys). -

Primary dilated cardiomyopathy Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Sep 06, 2013

The Glu82Lys variant in LMNA has been reported in at least 2 families with DCM a nd conduction system abnormalities, and segregated with disease in 8 affected re latives (Wang 2006, Wu 2010). It has not been identified in large population stu dies. Functional studies (in vitro) suggest an effect on protein function and mi ce carrying the variant exhibited clinical features of DCM (Wang 2006, Lu 2010, Sun 2010). In summary, this variant meets our criteria to be classified as patho genic (http://pcpgm.partners.org/LMM) based upon segregation studies, absence fr om controls, and functional evidence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
CardioboostCm	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.95	.;.;.;D;.
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.86
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;D;D;D;D
M_CAP	Pathogenic	0.61	D
MetaRNN	Pathogenic	0.93	D;D;D;D;D
MetaSVM	Pathogenic	0.93	D
MutationAssessor	Pathogenic	3.7	H;.;H;H;H
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-3.6	D;D;D;D;D
REVEL	Pathogenic	0.89
Sift	Pathogenic	0.0	D;D;D;D;D
Sift4G	Uncertain	0.0020	D;D;D;D;D
Polyphen		1.0	D;.;D;D;.
Vest4		0.94
MutPred		0.69		Gain of MoRF binding (P = 0.0025);Gain of MoRF binding (P = 0.0025);Gain of MoRF binding (P = 0.0025);Gain of MoRF binding (P = 0.0025);Gain of MoRF binding (P = 0.0025);
MVP		0.99
MPC		2.2
ClinPred		1.0	D
GERP RS		4.8
Varity_R		0.95
gMVP		1.0

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: rs59270054; hg19: chr1-156084953;