chr1-156135971-G-A

Position:

• chr1-156135971-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP2 PP3_Moderate

The NM_170707.4(LMNA):​c.1007G>A​(p.Arg336Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000103 in 1,461,710 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 Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000010 (0 hom.)
• Consequence: LMNA NM_170707.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:5 O:1
• Conservation: PhyloP100: 6.89

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 Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• 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, 0.927

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LMNA	NM_170707.4	c.1007G>A	p.Arg336Gln	missense_variant	6/12	ENST00000368300.9	NP_733821.1
LMNA	NM_005572.4	c.1007G>A	p.Arg336Gln	missense_variant	6/10	ENST00000677389.1	NP_005563.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LMNA	ENST00000368300.9	c.1007G>A	p.Arg336Gln	missense_variant	6/12	1	NM_170707.4	ENSP00000357283	P1
LMNA	ENST00000677389.1	c.1007G>A	p.Arg336Gln	missense_variant	6/10		NM_005572.4	ENSP00000503633

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000279 AC: 7 AN: 250572 Hom.: 0 AF XY: 0.0000295 AC XY: 4 AN XY: 135606

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000116

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000653

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000884

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000103 AC: 15 AN: 1461710 Hom.: 0 Cov.: 34 AF XY: 0.0000138 AC XY: 10 AN XY: 727160

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000894

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000464

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000277 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:5 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:2 Other:1

Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Dec 01, 2023	LMNA: PM1, PS4:Supporting -
not provided, no classification provided	literature only	Epithelial Biology; Institute of Medical Biology, Singapore	-	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Athena Diagnostics	Dec 21, 2021	- -

Charcot-Marie-Tooth disease type 2 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 06, 2023

This variant is present in population databases (rs58105277, gnomAD 0.01%). For these reasons, this variant has been classified as Pathogenic. 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: 66758). This missense change has been observed in individuals with Emery-Dreifuss muscular dystrophy and dilated cardiomyopathy (PMID: 29693488). This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 336 of the LMNA protein (p.Arg336Gln). -

Primary dilated cardiomyopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Dec 13, 2023

This missense variant replaces arginine with glutamine at codon 336 of the lamin A/C proteins. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in individuals affected with Emery Dreifuss Muscular Dystrophy and cardiac involvement (PMID: 10739764, 14659775, 29693488). This variant has been identified in 7/250572 chromosomes 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. -

Hutchinson-Gilford syndrome;C0410190:Emery-Dreifuss muscular dystrophy 2, autosomal dominant;C0796031:Dilated cardiomyopathy-hypergonadotropic hypogonadism syndrome;C1449563:Dilated cardiomyopathy 1A;C1720860:Familial partial lipodystrophy, Dunnigan type;C1854154:Charcot-Marie-Tooth disease type 2B1;C1857829:Heart-hand syndrome, Slovenian type;C2750035:Emery-Dreifuss muscular dystrophy 3, autosomal recessive;C2750785:Congenital muscular dystrophy due to LMNA mutation;C5399785:Mandibuloacral dysplasia with type A lipodystrophy;C5676942:Restrictive dermopathy 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Nov 02, 2021

- -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 14, 2020

The p.R336Q variant (also known as c.1007G>A), located in coding exon 6 of the LMNA gene, results from a G to A substitution at nucleotide position 1007. The arginine at codon 336 is replaced by glutamine, an amino acid with highly similar properties. This alteration has been detected in multiple patients with Emery-Dreifuss muscular dystrophy, but was also detected in several unaffected individuals (Raffaele Di Barletta M et al. Am. J. Hum. Genet., 2000 Apr;66:1407-12; Sanna T et al. Eur. Heart J., 2003 Dec;24:2227-36; Peretto G et al. Ann. Intern. Med., 2019 10;171:458-463; Bernasconi P et al. Nucleus, 2018 01;9:292-304; Park J et al. Genet. Med., 2020 01;22:102-111). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
CardioboostCm	Benign	0.022
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	30
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.82	.;.;.;D;.;.;.;.
Eigen	Uncertain	0.20
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Benign	0.84	T;T;T;T;T;D;T;D
M_CAP	Pathogenic	0.39	D
MetaRNN	Pathogenic	0.93	D;D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.064	T
MutationAssessor	Benign	1.9	L;.;L;L;L;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.62	T
PROVEAN	Benign	-2.0	N;N;N;N;N;N;N;N
REVEL	Pathogenic	0.66
Sift	Benign	0.18	T;T;T;T;T;T;T;T
Sift4G	Benign	0.17	T;T;T;T;T;T;T;T
Polyphen		0.028	B;.;B;B;.;.;B;.
Vest4		0.83
MutPred		0.81		Loss of MoRF binding (P = 0.0182);Loss of MoRF binding (P = 0.0182);Loss of MoRF binding (P = 0.0182);Loss of MoRF binding (P = 0.0182);Loss of MoRF binding (P = 0.0182);.;.;.;
MVP		0.97
MPC		1.6
ClinPred		0.27	T
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.9
Varity_R		0.43
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

LitVar

Other links and lift over

dbSNP: rs58105277; hg19: chr1-156105762;