chr8-143921870-G-A

Position:

• chr8-143921870-G-A

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_201384.3(PLEC):​c.7951C>T​(p.Arg2651Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00072 in 1,602,260 control chromosomes in the GnomAD database, including 16 homozygotes. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R2651Q) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.00083 (2 hom., cov: 34)
  • Exomes 𝑓: 0.00071 (14 hom.)
• Consequence: PLEC NM_201384.3 missense
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:6
• Conservation: PhyloP100: 2.65

Genes affected

PLEC (HGNC:9069): (plectin) Plectin is a prominent member of an important family of structurally and in part functionally related proteins, termed plakins or cytolinkers, that are capable of interlinking different elements of the cytoskeleton. Plakins, with their multi-domain structure and enormous size, not only play crucial roles in maintaining cell and tissue integrity and orchestrating dynamic changes in cytoarchitecture and cell shape, but also serve as scaffolding platforms for the assembly, positioning, and regulation of signaling complexes (reviewed in PMID: 9701547, 11854008, and 17499243). Plectin is expressed as several protein isoforms in a wide range of cell types and tissues from a single gene located on chromosome 8 in humans (PMID: 8633055, 8698233). Until 2010, this locus was named plectin 1 (symbol PLEC1 in human; Plec1 in mouse and rat) and the gene product had been referred to as "hemidesmosomal protein 1" or "plectin 1, intermediate filament binding 500kDa". These names were superseded by plectin. The plectin gene locus in mouse on chromosome 15 has been analyzed in detail (PMID: 10556294, 14559777), revealing a genomic exon-intron organization with well over 40 exons spanning over 62 kb and an unusual 5' transcript complexity of plectin isoforms. Eleven exons (1-1j) have been identified that alternatively splice directly into a common exon 2 which is the first exon to encode plectin's highly conserved actin binding domain (ABD). Three additional exons (-1, 0a, and 0) splice into an alternative first coding exon (1c), and two additional exons (2alpha and 3alpha) are optionally spliced within the exons encoding the acting binding domain (exons 2-8). Analysis of the human locus has identified eight of the eleven alternative 5' exons found in mouse and rat (PMID: 14672974); exons 1i, 1j and 1h have not been confirmed in human. Furthermore, isoforms lacking the central rod domain encoded by exon 31 have been detected in mouse (PMID:10556294), rat (PMID: 9177781), and human (PMID: 11441066, 10780662, 20052759). The short alternative amino-terminal sequences encoded by the different first exons direct the targeting of the various isoforms to distinct subcellular locations (PMID: 14559777). As the expression of specific plectin isoforms was found to be dependent on cell type (tissue) and stage of development (PMID: 10556294, 12542521, 17389230) it appears that each cell type (tissue) contains a unique set (proportion and composition) of plectin isoforms, as if custom-made for specific requirements of the particular cells. Concordantly, individual isoforms were found to carry out distinct and specific functions (PMID: 14559777, 12542521, 18541706). In 1996, a number of groups reported that patients suffering from epidermolysis bullosa simplex with muscular dystrophy (EBS-MD) lacked plectin expression in skin and muscle tissues due to defects in the plectin gene (PMID: 8698233, 8941634, 8636409, 8894687, 8696340). Two other subtypes of plectin-related EBS have been described: EBS-pyloric atresia (PA) and EBS-Ogna. For reviews of plectin-related diseases see PMID: 15810881, 19945614. Mutations in the plectin gene related to human diseases should be named based on the position in NM_000445 (variant 1, isoform 1c), unless the mutation is located within one of the other alternative first exons, in which case the position in the respective Reference Sequence should be used. [provided by RefSeq, Aug 2011]

ACMG classification

Verdict is Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.006946206).
• BP6: Variant 8-143921870-G-A is Benign according to our data. Variant chr8-143921870-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 287621.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr8-143921870-G-A is described in Lovd as [Likely_benign].
• BS1: Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.000834 (127/152348) while in subpopulation SAS AF= 0.00704 (34/4830). AF 95% confidence interval is 0.00518. There are 2 homozygotes in gnomad4. There are 79 alleles in male gnomad4 subpopulation. Median coverage is 34. This position pass quality control queck.
• BS2: High Homozygotes in GnomAd4 at 2 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
PLEC	NM_201384.3	c.7951C>T	p.Arg2651Trp	missense_variant	32/32	ENST00000345136.8
PLEC	NM_201378.4	c.7909C>T	p.Arg2637Trp	missense_variant	32/32	ENST00000356346.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PLEC	ENST00000345136.8	c.7951C>T	p.Arg2651Trp	missense_variant	32/32	1	NM_201384.3
PLEC	ENST00000356346.7	c.7909C>T	p.Arg2637Trp	missense_variant	32/32	1	NM_201378.4

Frequencies

GnomAD3 genomes AF: 0.000834 AC: 127 AN: 152230 Hom.: 2 Cov.: 34

Gnomad AFR AF: 0.0000723

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00438

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00703

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.000294

Gnomad OTH AF: 0.000956

GnomAD3 exomes AF: 0.00136 AC: 312 AN: 229204 Hom.: 3 AF XY: 0.00164 AC XY: 208 AN XY: 126910

Gnomad AFR exome AF: 0.0000723

Gnomad AMR exome AF: 0.00184

Gnomad ASJ exome AF: 0.000103

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00688

Gnomad FIN exome AF: 0.0000700

Gnomad NFE exome AF: 0.000290

Gnomad OTH exome AF: 0.00138

GnomAD4 exome AF: 0.000708 AC: 1026 AN: 1449912 Hom.: 14 Cov.: 79 AF XY: 0.000903 AC XY: 652 AN XY: 721818

Gnomad4 AFR exome AF: 0.000239

Gnomad4 AMR exome AF: 0.00172

Gnomad4 ASJ exome AF: 0.000153

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00761

Gnomad4 FIN exome AF: 0.0000237

Gnomad4 NFE exome AF: 0.000165

Gnomad4 OTH exome AF: 0.00119

GnomAD4 genome AF: 0.000834 AC: 127 AN: 152348 Hom.: 2 Cov.: 34 AF XY: 0.00106 AC XY: 79 AN XY: 74504

Gnomad4 AFR AF: 0.0000721

Gnomad4 AMR AF: 0.00438

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00704

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000294

Gnomad4 OTH AF: 0.000946

Alfa AF: 0.000348 Hom.: 0

Bravo AF: 0.000737

ESP6500AA AF: 0.000237 AC: 1

ESP6500EA AF: 0.000119 AC: 1

ExAC AF: 0.00118 AC: 142

Asia WGS AF: 0.00173 AC: 6 AN: 3478

EpiCase AF: 0.000818

EpiControl AF: 0.000534

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:2

Benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Apr 20, 2020	- -
Likely benign, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Jun 15, 2016	- -

not provided Benign:2

Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 27, 2020	- -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Jul 01, 2024	PLEC: BP4, BS2 -

Epidermolysis bullosa simplex, Ogna type;C2677349:Epidermolysis bullosa simplex 5C, with pyloric atresia;C2931072:Epidermolysis bullosa simplex 5B, with muscular dystrophy;C3150989:Autosomal recessive limb-girdle muscular dystrophy type 2Q;C4225309:Epidermolysis bullosa simplex with nail dystrophy Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 08, 2024

- -

PLEC-related disorder Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Dec 10, 2019

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.40	T
BayesDel_noAF	Benign	-0.34
CADD	Benign	23
DANN	Uncertain	0.98
DEOGEN2	Benign	0.24	.;.;.;.;T;.;.;.;.;.
Eigen	Benign	-0.18
Eigen_PC	Benign	-0.15
FATHMM_MKL	Benign	0.72	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.089	D
MetaRNN	Benign	0.0069	T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.87	T
MutationAssessor	Benign	0.69	.;.;.;.;N;.;.;.;.;.
MutationTaster	Benign	1.0	N;N;N;N;N;N;N;N;N
PrimateAI	Benign	0.29	T
PROVEAN	Benign	-1.4	N;N;N;N;N;N;N;N;.;N
REVEL	Benign	0.18
Sift	Uncertain	0.0040	D;D;D;D;D;D;D;D;.;D
Sift4G	Uncertain	0.011	D;D;D;D;D;D;D;D;.;D
Polyphen		0.83	P;P;P;P;P;P;P;P;.;.
Vest4		0.33
MVP		0.47
ClinPred		0.033	T
GERP RS		4.0
Varity_R		0.12
gMVP		0.71

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: rs145977158; hg19: chr8-144996038;