chr18-23949925-G-A

Position:

chr18-23949925-G-A

Variant summary

Our verdict is Pathogenic. Variant got 22 ACMG points: 22P and 0B. PVS1PM2PP3_StrongPP5_Very_Strong

The NM_198129.4(LAMA3):c.9511+1G>A variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000161 in 1,614,000 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000017 ( 0 hom. )

Consequence

LAMA3
NM_198129.4 splice_donor

Scores

Splicing: ADA: 1.000

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:2

Conservation

PhyloP100: 8.08

Variant links:

Genes affected

LAMA3 (HGNC:6483): (laminin subunit alpha 3) The protein encoded by this gene belongs to the laminin family of secreted molecules. Laminins are heterotrimeric molecules that consist of alpha, beta, and gamma subunits that assemble through a coiled-coil domain. Laminins are essential for formation and function of the basement membrane and have additional functions in regulating cell migration and mechanical signal transduction. This gene encodes an alpha subunit and is responsive to several epithelial-mesenchymal regulators including keratinocyte growth factor, epidermal growth factor and insulin-like growth factor. Mutations in this gene have been identified as the cause of Herlitz type junctional epidermolysis bullosa and laryngoonychocutaneous syndrome. Alternative splicing and alternative promoter usage result in multiple transcript variants. [provided by RefSeq, Dec 2014]

LAMA3 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 22 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

PP5

Variant 18-23949925-G-A is Pathogenic according to our data. Variant chr18-23949925-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 552174.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr18-23949925-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LAMA3	NM_000227.6 linkuse as main transcript	c.4684+1G>A		splice_donor_variant		ENST00000269217.11
LAMA3	NM_198129.4 linkuse as main transcript	c.9511+1G>A		splice_donor_variant		ENST00000313654.14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LAMA3	ENST00000269217.11 linkuse as main transcript	c.4684+1G>A		splice_donor_variant		1	NM_000227.6		Q16787-1
LAMA3	ENST00000313654.14 linkuse as main transcript	c.9511+1G>A		splice_donor_variant		1	NM_198129.4	P1	Q16787-2

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152112

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251480

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135912

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000171

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.0000179

AC XY:

AN XY:

727248

show subpopulations

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:

0.0000225

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152112

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74278

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Junctional epidermolysis bullosa gravis of Herlitz

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Sep 18, 2017	Variant summary: The LAMA3 c.4684+1G>A variant (also known as 4651+1G>A) involves the alteration of a conserved intronic nucleotide. One in silico tool predicts a damaging outcome for this variant. 4/5 splice prediction tools predict the complete loss of a canonical splice donor site. These predictions have been confirmed by immunoblotting of cell lysates from cultured keratinocytes derived from a patient showing the amount of chain expressed by the patient was <2% of normal (Gostynska_2017). This variant was found in 1/246262 control chromosomes at a frequency of 0.0000041, which does not exceed the estimated maximal expected allele frequency of a pathogenic LAMA3 variant (0.0004523). In addition, the variant has been reported in multiple affected individuals in the literature. Taken together, this variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	May 24, 2017	- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.29

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

1.2

Eigen_PC

Pathogenic

1.0

FATHMM_MKL

Uncertain

0.96

MutationTaster

Benign

1.0

D;D;D;D

GERP RS

5.7

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.94

SpliceAI score (max)

1.0

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.21

Position offset: 45

DS_DL_spliceai

1.0

Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over