4-54731930-G-T

Variant names:

• chr4-54731930-G-T
• rs760112920
• NM_000222.3:c.2293G>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 3P and 5B. PP2 PP3_Moderate BS1_Supporting BS2

The NM_000222.3(KIT):​c.2293G>T​(p.Asp765Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000062 in 1,613,536 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D765G) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000039 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: KIT NM_000222.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4 O:1
• Conservation: PhyloP100: 7.98
• Publications: 0 publications found

Genes affected

KIT (HGNC:6342): (KIT proto-oncogene, receptor tyrosine kinase) This gene encodes a receptor tyrosine kinase. This gene was initially identified as a homolog of the feline sarcoma viral oncogene v-kit and is often referred to as proto-oncogene c-Kit. The canonical form of this glycosylated transmembrane protein has an N-terminal extracellular region with five immunoglobulin-like domains, a transmembrane region, and an intracellular tyrosine kinase domain at the C-terminus. Upon activation by its cytokine ligand, stem cell factor (SCF), this protein phosphorylates multiple intracellular proteins that play a role in in the proliferation, differentiation, migration and apoptosis of many cell types and thereby plays an important role in hematopoiesis, stem cell maintenance, gametogenesis, melanogenesis, and in mast cell development, migration and function. This protein can be a membrane-bound or soluble protein. Mutations in this gene are associated with gastrointestinal stromal tumors, mast cell disease, acute myelogenous leukemia, and piebaldism. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2020]

KIT Gene-Disease associations (from GenCC):

• gastrointestinal stromal tumor

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet, ClinGen, Ambry Genetics
• piebaldism

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp
• cutaneous mastocytosis

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• mastocytosis

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Genomics England PanelApp, Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PP2: Missense variant in the KIT gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 54 curated pathogenic missense variants (we use a threshold of 10). The gene has 7 curated benign missense variants. Gene score misZ: 2.5806 (below the threshold of 3.09). Trascript score misZ: 4.1549 (above the threshold of 3.09). GenCC associations: The gene is linked to cutaneous mastocytosis, gastrointestinal stromal tumor, mastocytosis, piebaldism.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.898
• BS1: Variant frequency is greater than expected in population amr. GnomAd4 allele frequency = 0.0000395 (6/151982) while in subpopulation AMR AF = 0.000394 (6/15238). AF 95% confidence interval is 0.000171. There are 0 homozygotes in GnomAd4. There are 0 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
• BS2: High AC in GnomAd4 at 6 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000222.3. 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
	KIT	NM_000222.3	MANE Select	c.2293G>T	p.Asp765Tyr	missense	Exon 16 of 21	NP_000213.1
	KIT	NM_001385284.1		c.2296G>T	p.Asp766Tyr	missense	Exon 16 of 21	NP_001372213.1
	KIT	NM_001385290.1		c.2293G>T	p.Asp765Tyr	missense	Exon 16 of 21	NP_001372219.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KIT	ENST00000288135.6	TSL:1 MANE Select	c.2293G>T	p.Asp765Tyr	missense	Exon 16 of 21	ENSP00000288135.6
	KIT	ENST00000412167.7	TSL:1	c.2281G>T	p.Asp761Tyr	missense	Exon 16 of 21	ENSP00000390987.3
	KIT	ENST00000687109.1		c.2296G>T	p.Asp766Tyr	missense	Exon 16 of 21	ENSP00000509371.1

Frequencies

GnomAD3 genomes AF: 0.0000395 AC: 6 AN: 151982 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000394

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

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: 251380 AF XY: 0.00

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461554 Hom.: 0 Cov.: 34 AF XY: 0.00000413 AC XY: 3 AN XY: 727096

African (AFR) AF: 0.00 AC: 0 AN: 33464

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26118

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111744

Other (OTH) AF: 0.0000662 AC: 4 AN: 60388

GnomAD4 genome AF: 0.0000395 AC: 6 AN: 151982 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74218

African (AFR) AF: 0.00 AC: 0 AN: 41392

American (AMR) AF: 0.000394 AC: 6 AN: 15238

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5184

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10576

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 67982

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.00000824 AC: 1

Asia WGS AF: 0.00173 AC: 6 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Gastrointestinal stromal tumor Uncertain:2

Jan 30, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with tyrosine, which is neutral and polar, at codon 765 of the KIT protein (p.Asp765Tyr). This variant is present in population databases (rs760112920, gnomAD no frequency). This variant has not been reported in the literature in individuals affected with KIT-related conditions. ClinVar contains an entry for this variant (Variation ID: 458915). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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.

Mar 06, 2024

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

KIT-related disorder Uncertain:1

Jul 13, 2023

PreventionGenetics, part of Exact Sciences

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The KIT c.2293G>T variant is predicted to result in the amino acid substitution p.Asp765Tyr. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.0% of alleles in individuals of African descent in gnomAD (http://gnomad.broadinstitute.org/variant/4-55598096-G-T). It is interpreted as uncertain significance in ClinVar (https://preview.ncbi.nlm.nih.gov/clinvar/variation/458915/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence.

Hereditary cancer-predisposing syndrome Uncertain:1

Dec 04, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.D765Y variant (also known as c.2293G>T), located in coding exon 16 of the KIT gene, results from a G to T substitution at nucleotide position 2293. The aspartic acid at codon 765 is replaced by tyrosine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear.

Mastocytosis;C0080024:Piebaldism;C0238198:Gastrointestinal stromal tumor Other:1

GenomeConnect - Invitae Patient Insights Network

Significance: not provided

Review Status: no classification provided

Collection Method: phenotyping only

Variant classified as Uncertain significance and reported on 03-17-2021 by Invitae. GenomeConnect-InvitaePIN assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. Registry team members make no attempt to reinterpret the clinical significance of the variant. Phenotypic details are available under supporting information.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.56
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.33
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.92	D
Eigen	Pathogenic	0.71
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.87	D
M_CAP	Uncertain	0.19	D
MetaRNN	Pathogenic	0.90	D
MetaSVM	Uncertain	0.76	D
MutationAssessor	Benign	1.7	L
PhyloP100		8.0
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-6.9	D
REVEL	Pathogenic	0.70
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0020	D
Polyphen		1.0	D
Vest4		0.77
MutPred		0.57		Loss of disorder (P = 0.0773)
MVP		0.96
MPC		1.5
ClinPred		0.99	D
GERP RS		6.0
Varity_R		0.83
gMVP		0.86
Mutation Taster		=5/95	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: rs760112920; hg19: chr4-55598096;