18-23833905-T-A

Position:

• chr18-23833905-T-A

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_198129.4(LAMA3):​c.2901T>A​(p.Ala967=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. A967A) has been classified as Benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: LAMA3 NM_198129.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.667

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]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.83).
• BP7: Synonymous conserved (PhyloP=-0.667 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
LAMA3	NM_198129.4	c.2901T>A	p.Ala967=	synonymous_variant	24/75	ENST00000313654.14	NP_937762.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
LAMA3	ENST00000313654.14	c.2901T>A	p.Ala967=	synonymous_variant	24/75	1	NM_198129.4	ENSP00000324532	P1
LAMA3	ENST00000399516.7	c.2901T>A	p.Ala967=	synonymous_variant	24/74	1		ENSP00000382432
LAMA3	ENST00000591749.1	n.142T>A		non_coding_transcript_exon_variant	2/3	4
LAMA3	ENST00000592519.1			upstream_gene_variant		3		ENSP00000467662

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 55

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	4.5
DANN	Benign	0.69

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: rs9962023; hg19: chr18-21413869;