1-114716109-C-G

Variant names:

• chr1-114716109-C-G
• rs121913248
• NM_002524.5:c.52G>C

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_002524.5(NRAS):​c.52G>C​(p.Ala18Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,242 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. A18A) has been classified as Likely benign. The gene NRAS is included in the ClinGen Criteria Specification Registry.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: NRAS NM_002524.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.91
• Publications: 49 publications found

Genes affected

NRAS (HGNC:7989): (NRAS proto-oncogene, GTPase) This is an N-ras oncogene encoding a membrane protein that shuttles between the Golgi apparatus and the plasma membrane. This shuttling is regulated through palmitoylation and depalmitoylation by the ZDHHC9-GOLGA7 complex. The encoded protein, which has intrinsic GTPase activity, is activated by a guanine nucleotide-exchange factor and inactivated by a GTPase activating protein. Mutations in this gene have been associated with somatic rectal cancer, follicular thyroid cancer, autoimmune lymphoproliferative syndrome, Noonan syndrome, and juvenile myelomonocytic leukemia. [provided by RefSeq, Jun 2011]

NRAS Gene-Disease associations (from GenCC):

• Noonan syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• Noonan syndrome 6

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• cardiofaciocutaneous syndrome

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: ClinGen, Genomics England PanelApp
• Costello syndrome

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• Noonan syndrome with multiple lentigines

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• Noonan syndrome-like disorder with loose anagen hair

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Specifications for NRAS are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PM1: In a hotspot region, there are 11 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_002524.5
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 30 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Gene score misZ: 1.7139 (below the threshold of 3.09). Trascript score misZ: 2.2391 (below the threshold of 3.09). GenCC associations: The gene is linked to Noonan syndrome with multiple lentigines, Noonan syndrome 6, cardiofaciocutaneous syndrome, Noonan syndrome-like disorder with loose anagen hair, Noonan syndrome, Costello syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.926

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002524.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	NRAS	NM_002524.5	MANE Select	c.52G>C	p.Ala18Pro	missense	Exon 2 of 7	NP_002515.1	Q5U091

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	NRAS	ENST00000369535.5	TSL:1 MANE Select	c.52G>C	p.Ala18Pro	missense	Exon 2 of 7	ENSP00000358548.4	P01111
	NRAS	ENST00000899430.1		c.52G>C	p.Ala18Pro	missense	Exon 2 of 8	ENSP00000569489.1
	NRAS	ENST00000931010.1		c.52G>C	p.Ala18Pro	missense	Exon 2 of 7	ENSP00000601069.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152124 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251494 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152242 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74430

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41550

American (AMR) AF: 0.00 AC: 0 AN: 15296

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3464

East Asian (EAS) AF: 0.000193 AC: 1 AN: 5180

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10608

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68004

Other (OTH) AF: 0.00 AC: 0 AN: 2110

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.33
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.82	D
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.89	D
M_CAP	Uncertain	0.18	D
MetaRNN	Pathogenic	0.93	D
MetaSVM	Uncertain	0.60	D
MutationAssessor	Pathogenic	3.6	H
PhyloP100		7.9
PrimateAI	Pathogenic	0.90	D
PROVEAN	Uncertain	-4.3	D
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.96
MVP		0.87
MPC		2.2
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.99
gMVP		0.99
Mutation Taster		=15/85	disease causing

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: rs121913248; hg19: chr1-115258730;