5-87378512-A-G

Position:

• chr5-87378512-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP2

The NM_002890.3(RASA1):​c.2461A>G​(p.Ile821Val) 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 benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: RASA1 NM_002890.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.46

Genes affected

RASA1 (HGNC:9871): (RAS p21 protein activator 1) The protein encoded by this gene is located in the cytoplasm and is part of the GAP1 family of GTPase-activating proteins. The gene product stimulates the GTPase activity of normal RAS p21 but not its oncogenic counterpart. Acting as a suppressor of RAS function, the protein enhances the weak intrinsic GTPase activity of RAS proteins resulting in the inactive GDP-bound form of RAS, thereby allowing control of cellular proliferation and differentiation. Mutations leading to changes in the binding sites of either protein are associated with basal cell carcinomas. Mutations also have been associated with hereditary capillary malformations (CM) with or without arteriovenous malformations (AVM) and Parkes Weber syndrome. Alternative splicing results in two isoforms where the shorter isoform, lacking the N-terminal hydrophobic region but retaining the same activity, appears to be abundantly expressed in placental but not adult tissues. [provided by RefSeq, May 2012]

CCNH (HGNC:1594): (cyclin H) The protein encoded by this gene belongs to the highly conserved cyclin family, whose members are characterized by a dramatic periodicity in protein abundance through the cell cycle. Cyclins function as regulators of CDK kinases. Different cyclins exhibit distinct expression and degradation patterns which contribute to the temporal coordination of each mitotic event. This cyclin forms a complex with CDK7 kinase and ring finger protein MAT1. The kinase complex is able to phosphorylate CDK2 and CDC2 kinases, thus functions as a CDK-activating kinase (CAK). This cyclin and its kinase partner are components of TFIIH, as well as RNA polymerase II protein complexes. They participate in two different transcriptional regulation processes, suggesting an important link between basal transcription control and the cell cycle machinery. A pseudogene of this gene is found on chromosome 4. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Nov 2010]

CCNH (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a domain Ras-GAP (size 194) in uniprot entity RASA1_HUMAN there are 4 pathogenic changes around while only 1 benign (80%) in NM_002890.3
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), RASA1. . Gene score misZ 3.0984 (greater than the threshold 3.09). Trascript score misZ 3.5912 (greater than threshold 3.09). GenCC has associacion of gene with capillary malformation-arteriovenous malformation syndrome, Parkes Weber syndrome, Noonan syndrome, telangiectasia, hereditary hemorrhagic, type 1, capillary malformation-arteriovenous malformation 1.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RASA1	NM_002890.3	c.2461A>G	p.Ile821Val	missense_variant	18/25	ENST00000274376.11	NP_002881.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RASA1	ENST00000274376.11	c.2461A>G	p.Ile821Val	missense_variant	18/25	1	NM_002890.3	ENSP00000274376.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Capillary malformation-arteriovenous malformation syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 27, 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 sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. 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. ClinVar contains an entry for this variant (Variation ID: 464858). This variant has not been reported in the literature in individuals affected with RASA1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 821 of the RASA1 protein (p.Ile821Val). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Benign	0.0073	T
BayesDel_noAF	Benign	-0.23
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Benign	0.31	T;.;.;.
Eigen	Uncertain	0.39
Eigen_PC	Uncertain	0.47
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.92	D;D;D;D
M_CAP	Benign	0.041	D
MetaRNN	Benign	0.29	T;T;T;T
MetaSVM	Uncertain	0.044	D
MutationAssessor	Benign	1.1	L;.;.;.
PrimateAI	Pathogenic	0.82	D
PROVEAN	Benign	-0.68	N;N;N;N
REVEL	Uncertain	0.48
Sift	Benign	0.20	T;T;T;T
Sift4G	Benign	0.098	T;T;T;T
Polyphen		0.55	P;P;.;P
Vest4		0.26
MutPred		0.46		Gain of sheet (P = 0.1208);.;.;.;
MVP		0.76
MPC		1.4
ClinPred		0.89	D
GERP RS		5.1
Varity_R		0.18
gMVP		0.43

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.55		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.55		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1554049698; hg19: chr5-86674329;