chr18-6950864-C-A

Position:

• chr18-6950864-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_005559.4(LAMA1):​c.8315G>T​(p.Arg2772Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,850 control chromosomes in the GnomAD database, with no homozygous occurrence. 14/21 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R2772C) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: LAMA1 NM_005559.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.170

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 2 ACMG points.

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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LAMA1	NM_005559.4	c.8315G>T	p.Arg2772Leu	missense_variant	58/63	ENST00000389658.4	NP_005550.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LAMA1	ENST00000389658.4	c.8315G>T	p.Arg2772Leu	missense_variant	58/63	1	NM_005559.4	ENSP00000374309	P1
LAMA1	ENST00000488064.5	n.1722G>T		non_coding_transcript_exon_variant	9/14	2
LAMA1	ENST00000492048.5	n.1203G>T		non_coding_transcript_exon_variant	2/7	2
LAMA1	ENST00000579014.5	n.9330G>T		non_coding_transcript_exon_variant	57/62	2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461850 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727216

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	0.00031	T
BayesDel_noAF	Benign	-0.24
CADD	Benign	6.4
DANN	Benign	0.75
DEOGEN2	Benign	0.046	T
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.2
FATHMM_MKL	Benign	0.20	N
LIST_S2	Benign	0.84	T
M_CAP	Benign	0.038	D
MetaRNN	Uncertain	0.46	T
MetaSVM	Benign	-0.86	T
MutationAssessor	Benign	1.8	L
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.20	T
PROVEAN	Benign	-1.5	N
REVEL	Uncertain	0.44
Sift	Benign	0.30	T
Sift4G	Benign	0.75	T
Polyphen		0.18	B
Vest4		0.52
MutPred		0.74		Loss of sheet (P = 0.007);
MVP		0.42
MPC		0.19
ClinPred		0.10	T
GERP RS		-2.7
Varity_R		0.052
gMVP		0.45

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: rs548903685; hg19: chr18-6950863;