NM_001354604.2:c.1050G>C

Variant names:

• chr3-69959291-G-C
• rs201348324
• NM_001354604.2:c.1050G>C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_001354604.2(MITF):​c.1050G>C​(p.Lys350Asn) variant causes a missense change involving the alteration of a non-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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K350E) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MITF NM_001354604.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.91
• Publications: 0 publications found

Genes affected

MITF (HGNC:7105): (melanocyte inducing transcription factor) The protein encoded by this gene is a transcription factor that contains both basic helix-loop-helix and leucine zipper structural features. The encoded protein regulates melanocyte development and is responsible for pigment cell-specific transcription of the melanogenesis enzyme genes. Heterozygous mutations in the this gene cause auditory-pigmentary syndromes, such as Waardenburg syndrome type 2 and Tietz syndrome. [provided by RefSeq, Aug 2017]

MITF Gene-Disease associations (from GenCC):

• Tietz syndrome

  Inheritance: AD Classification: DEFINITIVE, MODERATE, SUPPORTIVE Submitted by: G2P, Orphanet, Ambry Genetics
• Waardenburg syndrome type 2

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• Waardenburg syndrome type 2A

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, G2P, Ambry Genetics
• melanoma, cutaneous malignant, susceptibility to, 8

  Inheritance: AD Classification: STRONG, MODERATE, LIMITED Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
• coloboma, osteopetrosis, microphthalmia, macrocephaly, albinism, and deafness

  Inheritance: AR Classification: STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P
• renal cell carcinoma

  Inheritance: AD Classification: MODERATE Submitted by: Genomics England PanelApp
• Waardenburg syndrome

  Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics
• Waardenburg-Shah syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 16 uncertain in NM_001354604.2
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.897

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MITF	NM_001354604.2	c.1050G>C	p.Lys350Asn	missense_variant	Exon 9 of 10	ENST00000352241.9	NP_001341533.1
MITF	NM_000248.4	c.729G>C	p.Lys243Asn	missense_variant	Exon 8 of 9	ENST00000394351.9	NP_000239.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MITF	ENST00000352241.9	c.1050G>C	p.Lys350Asn	missense_variant	Exon 9 of 10	1	NM_001354604.2	ENSP00000295600.8
MITF	ENST00000394351.9	c.729G>C	p.Lys243Asn	missense_variant	Exon 8 of 9	1	NM_000248.4	ENSP00000377880.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

MITF-related disorder Uncertain:1

Sep 13, 2022

PreventionGenetics, part of Exact Sciences

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The MITF c.729G>C variant is predicted to result in the amino acid substitution p.Lys243Asn. To our knowledge, this variant has not been reported in the literature or in a large population database (http://gnomad.broadinstitute.org), indicating this variant is rare. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.30
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.99	.;D;.;.;.;.;D;.;.;.
Eigen	Uncertain	0.48
Eigen_PC	Uncertain	0.36
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Pathogenic	1.0	.;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.67	D
MetaRNN	Pathogenic	0.90	D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.4	.;M;.;.;.;.;.;.;.;.
PhyloP100		2.9
PrimateAI	Pathogenic	0.91	D
PROVEAN	Pathogenic	-4.7	D;D;.;D;D;D;D;D;D;D
REVEL	Pathogenic	0.86
Sift	Pathogenic	0.0	D;D;.;D;D;D;D;D;D;D
Sift4G	Uncertain	0.0020	D;D;.;D;D;D;D;D;D;D
Polyphen		1.0	D;.;D;.;D;D;.;D;D;.
Vest4		0.97
MutPred		0.70		Gain of catalytic residue at K344 (P = 0.0188);.;Gain of catalytic residue at K344 (P = 0.0188);.;.;.;.;.;.;.;
MVP		0.97
MPC		1.0
ClinPred		1.0	D
GERP RS		2.2
Varity_R		0.93
gMVP		0.99
Mutation Taster		=3/97	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs201348324; hg19: chr3-70008442;