4-54727298-A-T

Variant names:

• chr4-54727298-A-T
• rs3822214
• NM_000222.3:c.1621A>T

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 3P and 7B. PM1 PP2 BP4_Moderate BP6 BS2

The NM_000222.3(KIT):​c.1621A>T​(p.Met541Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000123 in 1,461,790 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely benign in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M541T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: KIT NM_000222.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:2
• Conservation: PhyloP100: 1.03
• Publications: 249 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: Ambry Genetics, ClinGen, Genomics England PanelApp, Orphanet, Labcorp Genetics (formerly Invitae)
• piebaldism

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Ambry Genetics, G2P, Orphanet, Labcorp Genetics (formerly Invitae)
• 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 -4 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 4 benign, 22 uncertain in NM_000222.3
• 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 mastocytosis, piebaldism, gastrointestinal stromal tumor, cutaneous mastocytosis.
• BP4: Computational evidence support a benign effect (MetaRNN=0.12275258).
• BP6: Variant 4-54727298-A-T is Benign according to our data. Variant chr4-54727298-A-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 715131.
• BS2: High AC in GnomAdExome4 at 18 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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KIT	NM_000222.3	MANE Select	c.1621A>T	p.Met541Leu	missense	Exon 10 of 21	NP_000213.1	P10721-1
	KIT	NM_001385284.1		c.1624A>T	p.Met542Leu	missense	Exon 10 of 21	NP_001372213.1	A0A8I5KS03
	KIT	NM_001385290.1		c.1624A>T	p.Met542Leu	missense	Exon 10 of 21	NP_001372219.1	A0A8I5QKP7

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KIT	ENST00000288135.6	TSL:1 MANE Select	c.1621A>T	p.Met541Leu	missense	Exon 10 of 21	ENSP00000288135.6	P10721-1
	KIT	ENST00000412167.7	TSL:1	c.1612A>T	p.Met538Leu	missense	Exon 10 of 21	ENSP00000390987.3	A0A8J8Z860
	KIT	ENST00000687109.1		c.1624A>T	p.Met542Leu	missense	Exon 10 of 21	ENSP00000509371.1	A0A8I5KS03

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000796 AC: 2 AN: 251206 AF XY: 0.0000147

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: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000123 AC: 18 AN: 1461790 Hom.: 0 Cov.: 33 AF XY: 0.0000124 AC XY: 9 AN XY: 727212

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.0000162 AC: 18 AN: 1111928

Other (OTH) AF: 0.00 AC: 0 AN: 60392

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 2686

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	-	1	Gastrointestinal stromal tumor (1)
-	-	1	Hereditary cancer-predisposing syndrome (1)
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.083
BayesDel_addAF	Uncertain	0.069	T
BayesDel_noAF	Benign	-0.14
CADD	Benign	16
DANN	Benign	0.47
DEOGEN2	Benign	0.23	T
Eigen	Benign	-0.94
Eigen_PC	Benign	-0.78
FATHMM_MKL	Benign	0.68	D
LIST_S2	Benign	0.75	T
M_CAP	Benign	0.024	T
MetaRNN	Benign	0.12	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-0.38	N
PhyloP100		1.0
PrimateAI	Benign	0.42	T
PROVEAN	Benign	0.22	N
REVEL	Uncertain	0.42
Sift	Benign	0.80	T
Sift4G	Benign	0.81	T
Polyphen		0.012	B
Vest4		0.45
MutPred		0.14		Gain of catalytic residue at M541 (P = 0.0666)
MVP		0.97
MPC		0.41
ClinPred		0.020	T
GERP RS		1.8
Varity_R		0.059
gMVP		0.69
Mutation Taster		=39/40	polymorphism

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: rs3822214; hg19: chr4-55593464;