chr3-39407753-A-G

Position:

• chr3-39407753-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2 PP2 PP3_Strong

The NM_002295.6(RPSA):​c.100A>G​(p.Met34Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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)
• Consequence: RPSA NM_002295.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.74

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.

• 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, 0.947

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RPSA	NM_002295.6	c.100A>G	p.Met34Val	missense_variant	2/7	ENST00000301821.11
RPSA	NM_001304288.2	c.100A>G	p.Met34Val	missense_variant	2/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RPSA	ENST00000301821.11	c.100A>G	p.Met34Val	missense_variant	2/7	1	NM_002295.6	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

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

GeneDx

Oct 18, 2017

The M34V variant in the RPSA gene has not been reported previously as a pathogenic variant, nor as a benign variant, to our knowledge. The M34V variant is not observed in large population cohorts (Lek et al., 2016). The M34V variant is a conservative amino acid substitution, which is not likely to impact secondary protein structure as these residues share similar properties. However, this substitution occurs at a position that is conserved across species, and in silico analysis predicts this variant is probably damaging to the protein structure/function. We interpret M34V as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Pathogenic	0.23	D
BayesDel_noAF	Uncertain	0.090
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.93	D;.;T;D
Eigen	Uncertain	0.49
Eigen_PC	Uncertain	0.51
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.77	T;T;T;T
M_CAP	Benign	0.065	D
MetaRNN	Pathogenic	0.95	D;D;D;D
MetaSVM	Benign	-0.65	T
MutationAssessor	Uncertain	2.7	M;.;.;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-3.2	D;D;D;.
REVEL	Uncertain	0.51
Sift	Uncertain	0.015	D;D;D;.
Sift4G	Uncertain	0.017	D;D;D;D
Polyphen		0.25	B;B;.;.
Vest4		0.89
MutPred		0.89		Loss of disorder (P = 0.2593);Loss of disorder (P = 0.2593);Loss of disorder (P = 0.2593);Loss of disorder (P = 0.2593);
MVP		0.75
MPC		1.4
ClinPred		0.98	D
GERP RS		4.8
Varity_R		0.72
gMVP		0.93

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.12		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: rs1553613060; hg19: chr3-39449244;