chr18-6943258-C-T

Position:

chr18-6943258-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_005559.4(LAMA1):c.8989G>A(p.Ala2997Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000266 in 1,614,078 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

LAMA1
NM_005559.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: -0.311

Variant links:

Genes affected

LAMA1 (HGNC:6481): (laminin subunit alpha 1) This gene encodes one of the alpha 1 subunits of laminin. The laminins are a family of extracellular matrix glycoproteins that have a heterotrimeric structure consisting of an alpha, beta and gamma chain. These proteins make up a major component of the basement membrane and have been implicated in a wide variety of biological processes including cell adhesion, differentiation, migration, signaling, neurite outgrowth and metastasis. Mutations in this gene may be associated with Poretti-Boltshauser syndrome. [provided by RefSeq, Sep 2014]

LAMA1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.0569067).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LAMA1	NM_005559.4 linkuse as main transcript	c.8989G>A	p.Ala2997Thr	missense_variant	62/63	ENST00000389658.4	NP_005550.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris
LAMA1	ENST00000389658.4 linkuse as main transcript	c.8989G>A	p.Ala2997Thr	missense_variant	62/63	1	NM_005559.4	ENSP00000374309	P1
LAMA1	ENST00000488064.5 linkuse as main transcript	n.2396G>A		non_coding_transcript_exon_variant	13/14	2
LAMA1	ENST00000492048.5 linkuse as main transcript	n.1877G>A		non_coding_transcript_exon_variant	6/7	2
LAMA1	ENST00000579014.5 linkuse as main transcript	n.10004G>A		non_coding_transcript_exon_variant	61/62	2

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152186

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251490

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135920

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:

0.0000924

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000274

AC:

AN:

1461892

Hom.:

Cov.:

AF XY:

0.0000234

AC XY:

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

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:

0.0000374

Gnomad4 NFE exome

AF:

0.0000306

Gnomad4 OTH exome

AF:

0.0000497

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152186

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74340

show subpopulations

Gnomad4 AFR

AF:

0.0000241

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:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000540

Hom.:

Bravo

AF:

0.0000151

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 16, 2024

The c.8989G>A (p.A2997T) alteration is located in exon 62 (coding exon 62) of the LAMA1 gene. This alteration results from a G to A substitution at nucleotide position 8989, causing the alanine (A) at amino acid position 2997 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 08, 2022

This variant has not been reported in the literature in individuals affected with LAMA1-related conditions. This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 2997 of the LAMA1 protein (p.Ala2997Thr). This variant is present in population databases (rs777813445, gnomAD 0.008%). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The threonine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.067

BayesDel_addAF

Benign

-0.22

BayesDel_noAF

Benign

-0.56

CADD

Benign

0.13

DANN

Benign

0.68

DEOGEN2

Benign

0.016

Eigen

Benign

-1.0

Eigen_PC

Benign

-1.1

FATHMM_MKL

Benign

0.030

LIST_S2

Benign

0.49

M_CAP

Benign

0.018

MetaRNN

Benign

0.057

MetaSVM

Benign

-0.94

MutationAssessor

Benign

0.35

MutationTaster

Benign

1.0

PrimateAI

Benign

0.25

PROVEAN

Benign

-0.050

REVEL

Benign

0.10

Sift

Benign

0.61

Sift4G

Benign

0.75

Polyphen

0.0030

Vest4

0.049

MVP

0.65

MPC

0.11

ClinPred

0.021

GERP RS

-3.1

Varity_R

0.018

gMVP

0.14

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

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