chr16-89919773-G-C

Variant names:

• chr16-89919773-G-C
• rs376670171
• NM_002386.4:c.515G>C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_002386.4(MC1R):​c.515G>C​(p.Ser172Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000206 in 1,456,252 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. S172I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: MC1R NM_002386.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.07
• Publications: 0 publications found

Genes affected

MC1R (HGNC:6929): (melanocortin 1 receptor) This intronless gene encodes the receptor protein for melanocyte-stimulating hormone (MSH). The encoded protein, a seven pass transmembrane G protein coupled receptor, controls melanogenesis. Two types of melanin exist: red pheomelanin and black eumelanin. Gene mutations that lead to a loss in function are associated with increased pheomelanin production, which leads to lighter skin and hair color. Eumelanin is photoprotective but pheomelanin may contribute to UV-induced skin damage by generating free radicals upon UV radiation. Binding of MSH to its receptor activates the receptor and stimulates eumelanin synthesis. This receptor is a major determining factor in sun sensitivity and is a genetic risk factor for melanoma and non-melanoma skin cancer. Over 30 variant alleles have been identified which correlate with skin and hair color, providing evidence that this gene is an important component in determining normal human pigment variation. [provided by RefSeq, Jul 2008]

ENSG00000198211 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.91

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MC1R	NM_002386.4	c.515G>C	p.Ser172Thr	missense_variant	Exon 1 of 1	ENST00000555147.2	NP_002377.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MC1R	ENST00000555147.2	c.515G>C	p.Ser172Thr	missense_variant	Exon 1 of 1	6	NM_002386.4	ENSP00000451605.1
ENSG00000198211	ENST00000556922.1	c.515G>C	p.Ser172Thr	missense_variant	Exon 1 of 5	2		ENSP00000451560.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000206 AC: 3 AN: 1456252 Hom.: 0 Cov.: 35 AF XY: 0.00000414 AC XY: 3 AN XY: 724644

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26124

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: 48098

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

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111802

Other (OTH) AF: 0.00 AC: 0 AN: 60320

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Melanoma, cutaneous malignant, susceptibility to, 5 Uncertain:1

Nov 06, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces serine, which is neutral and polar, with threonine, which is neutral and polar, at codon 172 of the MC1R protein (p.Ser172Thr). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with MC1R-related conditions. Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt MC1R protein function with a negative predictive value of 80%. 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.

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.17
BayesDel_addAF	Uncertain	0.012	T
BayesDel_noAF	Benign	-0.22
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Benign	0.0	.;T;T;.
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.51
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	D;.;D;D
M_CAP	Benign	0.051	D
MetaRNN	Pathogenic	0.91	D;D;D;D
MetaSVM	Benign	-0.43	T
MutationAssessor	Benign	0.0	.;M;M;.
PhyloP100		8.1
PROVEAN	Benign	-1.6	N;.;N;N
REVEL	Uncertain	0.35
Sift	Pathogenic	0.0	D;.;D;D
Sift4G	Benign	0.16	T;.;T;D
Vest4		0.67
ClinPred		0.99	D
GERP RS		4.7
Varity_R		0.54
gMVP		0.47
Mutation Taster		=60/40	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: rs376670171; hg19: chr16-89986181;