rs377516549

chr18-7007219-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_005559.4(LAMA1):c.4180C>T(p.Arg1394Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000186 in 1,614,014 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000018 (0 hom.)
• Consequence: LAMA1 NM_005559.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 4.86

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.3517642).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LAMA1	NM_005559.4	c.4180C>T	p.Arg1394Cys	missense_variant	29/63	ENST00000389658.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LAMA1	ENST00000389658.4	c.4180C>T	p.Arg1394Cys	missense_variant	29/63	1	NM_005559.4	P1
LAMA1	ENST00000579014.5	n.5195C>T		non_coding_transcript_exon_variant	28/62	2

Frequencies

GnomAD3 genomes AF: 0.0000263 AC: 4 AN: 152146 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000965

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: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000438 AC: 11 AN: 251270 Hom.: 0 AF XY: 0.0000589 AC XY: 8 AN XY: 135836

Gnomad AFR exome AF: 0.0000616

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000294

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000178 AC: 26 AN: 1461868 Hom.: 0 Cov.: 31 AF XY: 0.0000206 AC XY: 15 AN XY: 727234

Gnomad4 AFR exome AF: 0.0000597

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000450

Gnomad4 OTH exome AF: 0.000132

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152146 Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2 AN XY: 74318

Gnomad4 AFR AF: 0.0000965

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: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.0000529

ESP6500AA AF: 0.000227 AC: 1

ESP6500EA AF: 0.00 AC: 0

ExAC AF: 0.0000330 AC: 4

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Jan 03, 2022	This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 1394 of the LAMA1 protein (p.Arg1394Cys). This variant is present in population databases (rs377516549, gnomAD 0.03%). 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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 377158). This variant has not been reported in the literature in individuals affected with LAMA1-related conditions. -
Uncertain significance, criteria provided, single submitter	clinical testing	Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics	Nov 18, 2016	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Benign	-0.35	T
BayesDel_noAF	Benign	-0.44
Cadd	Uncertain	24
Dann	Uncertain	1.0
DEOGEN2	Benign	0.13	T
Eigen	Uncertain	0.37
Eigen_PC	Uncertain	0.29
FATHMM_MKL	Uncertain	0.76	D
LIST_S2	Benign	0.80	T
M_CAP	Benign	0.0058	T
MetaRNN	Benign	0.35	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Uncertain	2.6	M
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.32	T
PROVEAN	Uncertain	-3.0	D
REVEL	Benign	0.18
Sift	Benign	0.068	T
Sift4G	Uncertain	0.028	D
Polyphen		1.0	D
Vest4		0.38
MVP		0.47
MPC		0.49
ClinPred		0.38	T
GERP RS		5.8
Varity_R		0.082
gMVP		0.53

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: rs377516549; hg19: chr18-7007218;