3-39408657-C-G

Position:

• chr3-39408657-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_002295.6(RPSA):​c.185C>G​(p.Ala62Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,254 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: RPSA NM_002295.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.61

Genes affected

RPSA (HGNC:6502): (ribosomal protein SA) 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. Many of the effects of laminin are mediated through interactions with cell surface receptors. These receptors include members of the integrin family, as well as non-integrin laminin-binding proteins. This gene encodes a high-affinity, non-integrin family, laminin receptor 1. This receptor has been variously called 67 kD laminin receptor, 37 kD laminin receptor precursor (37LRP) and p40 ribosome-associated protein. The amino acid sequence of laminin receptor 1 is highly conserved through evolution, suggesting a key biological function. It has been observed that the level of the laminin receptor transcript is higher in colon carcinoma tissue and lung cancer cell line than their normal counterparts. Also, there is a correlation between the upregulation of this polypeptide in cancer cells and their invasive and metastatic phenotype. Multiple copies of this gene exist, however, most of them are pseudogenes thought to have arisen from retropositional events. Two alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_002295.6
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), RPSA. . Gene score misZ 2.4182 (greater than the threshold 3.09). Trascript score misZ 3.3111 (greater than threshold 3.09). GenCC has associacion of gene with familial isolated congenital asplenia.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.846

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RPSA	NM_002295.6	c.185C>G	p.Ala62Gly	missense_variant	3/7	ENST00000301821.11
RPSA	NM_001304288.2	c.185C>G	p.Ala62Gly	missense_variant	3/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RPSA	ENST00000301821.11	c.185C>G	p.Ala62Gly	missense_variant	3/7	1	NM_002295.6	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251470 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135916

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: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461254 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 726972

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 24, 2022

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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. This variant has not been reported in the literature in individuals affected with RPSA-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.0009%). This sequence change replaces alanine, which is neutral and non-polar, with glycine, which is neutral and non-polar, at codon 62 of the RPSA protein (p.Ala62Gly). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.76
BayesDel_addAF	Uncertain	0.012	T
BayesDel_noAF	Benign	-0.22
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.91	D;.;T;D
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.54
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D;D;D;D
M_CAP	Benign	0.059	D
MetaRNN	Pathogenic	0.85	D;D;D;D
MetaSVM	Benign	-0.52	T
MutationAssessor	Uncertain	2.6	M;.;.;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.85	D
PROVEAN	Uncertain	-3.5	D;D;D;.
REVEL	Uncertain	0.36
Sift	Uncertain	0.0010	D;D;D;.
Sift4G	Uncertain	0.021	D;D;D;D
Polyphen		0.17	B;P;.;.
Vest4		0.61
MutPred		0.72		Loss of stability (P = 0.0213);Loss of stability (P = 0.0213);Loss of stability (P = 0.0213);Loss of stability (P = 0.0213);
MVP		0.34
MPC		2.3
ClinPred		0.98	D
GERP RS		4.5
Varity_R		0.94
gMVP		0.84

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1197554509; hg19: chr3-39450148;