NM_002292.4:c.4924-35G>A

Variant names:

• chr3-49121895-C-T
• rs72936885
• NM_002292.4:c.4924-35G>A

Variant summary

Our verdict is Benign. The variant received -14 ACMG points: 0P and 14B. BP4_Strong BP6_Moderate BS1 BS2

The NM_002292.4(LAMB2):​c.4924-35G>A variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00307 in 1,613,630 control chromosomes in the GnomAD database, including 35 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.0078 (18 hom., cov: 33)
  • Exomes 𝑓: 0.0026 (17 hom.)
• Consequence: LAMB2 NM_002292.4 intron
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.543
• Publications: 1 publications found

Genes affected

LAMB2 (HGNC:6487): (laminin subunit beta 2) Laminins, a family of extracellular matrix glycoproteins, are the major noncollagenous constituent of basement membranes. They have been implicated in a wide variety of biological processes including cell adhesion, differentiation, migration, signaling, neurite outgrowth and metastasis. Laminins, composed of 3 non identical chains: laminin alpha, beta and gamma (formerly A, B1, and B2, respectively), form a cruciform structure consisting of 3 short arms, each formed by a different chain, and a long arm composed of all 3 chains. Each laminin chain is a multidomain protein encoded by a distinct gene. Several isoforms of each chain have been described. Different alpha, beta and gamma chain isomers combine to give rise to different heterotrimeric laminin isoforms which are designated by Arabic numerals in the order of their discovery, i.e. alpha1beta1gamma1 heterotrimer is laminin 1. The biological functions of the different chains and trimer molecules are largely unknown, but some of the chains have been shown to differ with respect to their tissue distribution, presumably reflecting diverse functions in vivo. This gene encodes the beta chain isoform laminin, beta 2. The beta 2 chain contains the 7 structural domains typical of beta chains of laminin, including the short alpha region. However, unlike beta 1 chain, beta 2 has a more restricted tissue distribution. It is enriched in the basement membrane of muscles at the neuromuscular junctions, kidney glomerulus and vascular smooth muscle. Transgenic mice in which the beta 2 chain gene was inactivated by homologous recombination, showed defects in the maturation of neuromuscular junctions and impairment of glomerular filtration. Alternative splicing involving a non consensus 5' splice site (gc) in the 5' UTR of this gene has been reported. It was suggested that inefficient splicing of this first intron, which does not change the protein sequence, results in a greater abundance of the unspliced form of the transcript than the spliced form. The full-length nature of the spliced transcript is not known. [provided by RefSeq, Aug 2011]

LAMB2 Gene-Disease associations (from GenCC):

• Pierson syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, PanelApp Australia, Orphanet
• LAMB2-related infantile-onset nephrotic syndrome

  Inheritance: AR Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Benign. The variant received -14 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.89).
• BP6: Variant 3-49121895-C-T is Benign according to our data. Variant chr3-49121895-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 1218980.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00782 (1192/152346) while in subpopulation AFR AF = 0.0227 (944/41572). AF 95% confidence interval is 0.0215. There are 18 homozygotes in GnomAd4. There are 553 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
• BS2: High Homozygotes in GnomAd4 at 18 AR gene

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002292.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LAMB2	NM_002292.4	MANE Select	c.4924-35G>A		intron	N/A	NP_002283.3

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	LAMB2	ENST00000305544.9	TSL:1 MANE Select	c.4924-35G>A		intron	N/A	ENSP00000307156.4
	LAMB2	ENST00000418109.5	TSL:1	c.4924-35G>A		intron	N/A	ENSP00000388325.1
	LAMB2	ENST00000467506.5	TSL:2	n.34-35G>A		intron	N/A

Frequencies

GnomAD3 genomes AF: 0.00783 AC: 1192 AN: 152228 Hom.: 18 Cov.: 33

Gnomad AFR AF: 0.0228

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00255

Gnomad ASJ AF: 0.000864

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00104

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.00266

Gnomad OTH AF: 0.00623

GnomAD2 exomes AF: 0.00374 AC: 938 AN: 251008 AF XY: 0.00323

Gnomad AFR exome AF: 0.0257

Gnomad AMR exome AF: 0.00142

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000109

Gnomad FIN exome AF: 0.00203

Gnomad NFE exome AF: 0.00357

Gnomad OTH exome AF: 0.00310

GnomAD4 exome AF: 0.00258 AC: 3765 AN: 1461284 Hom.: 17 Cov.: 33 AF XY: 0.00242 AC XY: 1756 AN XY: 726972

African (AFR) AF: 0.0233 AC: 780 AN: 33480

American (AMR) AF: 0.00152 AC: 68 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.000459 AC: 12 AN: 26136

East Asian (EAS) AF: 0.000101 AC: 4 AN: 39700

South Asian (SAS) AF: 0.0000348 AC: 3 AN: 86258

European-Finnish (FIN) AF: 0.00204 AC: 108 AN: 52832

Middle Eastern (MID) AF: 0.000520 AC: 3 AN: 5768

European-Non Finnish (NFE) AF: 0.00233 AC: 2596 AN: 1111998

Other (OTH) AF: 0.00316 AC: 191 AN: 60388

GnomAD4 genome AF: 0.00782 AC: 1192 AN: 152346 Hom.: 18 Cov.: 33 AF XY: 0.00742 AC XY: 553 AN XY: 74510

African (AFR) AF: 0.0227 AC: 944 AN: 41572

American (AMR) AF: 0.00255 AC: 39 AN: 15302

Ashkenazi Jewish (ASJ) AF: 0.000864 AC: 3 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00104 AC: 11 AN: 10626

Middle Eastern (MID) AF: 0.00340 AC: 1 AN: 294

European-Non Finnish (NFE) AF: 0.00266 AC: 181 AN: 68034

Other (OTH) AF: 0.00616 AC: 13 AN: 2110

Alfa AF: 0.00458 Hom.: 0

Bravo AF: 0.00845

Asia WGS AF: 0.00173 AC: 7 AN: 3478

ClinVar

ClinVar submissions as Germline

Significance: Likely benign

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	-	1	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.89
CADD	Benign	1.8
DANN	Benign	0.61
PhyloP100		-0.54
Mutation Taster		=100/0	polymorphism

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

Other links and lift over

dbSNP: rs72936885; hg19: chr3-49159328;