chr12-10997479-C-G

Position:

• chr12-10997479-C-G

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 2P and 6B. PM2 BP4_Strong BP6_Moderate

The NM_176889.4(TAS2R20):​c.397G>C​(p.Val133Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,756 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: TAS2R20 NM_176889.4 missense
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.677

Genes affected

TAS2R20 (HGNC:19109): (taste 2 receptor member 20) This gene encodes a member of the taste receptor two family of class C G-protein coupled receptors. Receptors of this family have a short extracellular N-terminus, seven transmembrane helices, three extracellular loops and three intracellular loops, and an intracellular C-terminus. Members of this family are expressed in a subset of taste receptor cells, where they function in bitter taste reception, as well as in non-gustatory cells including those of the brain, reproductive organs, respiratory system, and gastrointestinal system. This gene maps to the taste receptor gene cluster on chromosome 12p13. [provided by RefSeq, Jul 2016]

ENSG00000275778 (HGNC:):

PRH1 (HGNC:9366): (proline rich protein HaeIII subfamily 1) This gene encodes a member of the heterogeneous family of proline-rich salivary glycoproteins. The encoded preproprotein undergoes proteolytic processing to generate one or more mature isoforms before secretion from the parotid and submandibular/sublingual glands. Multiple distinct alleles of this locus including the parotid isoelectric-focusing variant slow (PIF-s), the parotid acidic protein (Pa), and the double band slow (Db-s) isoforms have been characterized. The reference genome encodes the Db-s allele. Certain alleles of this gene are associated with susceptibility to dental caries. This gene is located in a cluster of closely related salivary proline-rich proteins on chromosome 12. Co-transcription of this gene with adjacent genes has been observed. Alternate splicing of this gene results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Oct 2015]

ACMG classification

Verdict is Likely_benign. Variant got -4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.031675756).
• BP6: Variant 12-10997479-C-G is Benign according to our data. Variant chr12-10997479-C-G is described in ClinVar as [Likely_benign]. Clinvar id is 2231257.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TAS2R20	NM_176889.4	c.397G>C	p.Val133Leu	missense_variant	1/1	ENST00000538986.2	NP_795370.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TAS2R20	ENST00000538986.2	c.397G>C	p.Val133Leu	missense_variant	1/1	6	NM_176889.4	ENSP00000441624.1
ENSG00000275778	ENST00000703543.1	c.-125-23758G>C		intron_variant				ENSP00000515364.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250558 Hom.: 0 AF XY: 0.00000739 AC XY: 1 AN XY: 135382

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.0000995

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461756 Hom.: 0 Cov.: 47 AF XY: 0.00000275 AC XY: 2 AN XY: 727182

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 28, 2022

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.071
BayesDel_addAF	Benign	-0.33	T
BayesDel_noAF	Benign	-0.71
CADD	Benign	0.0030
DANN	Benign	0.46
DEOGEN2	Benign	0.0021	T
Eigen	Benign	-2.2
Eigen_PC	Benign	-2.1
FATHMM_MKL	Benign	0.00056	N
M_CAP	Benign	0.0032	T
MetaRNN	Benign	0.032	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-2.3	N
PrimateAI	Benign	0.21	T
PROVEAN	Benign	2.2	N
REVEL	Benign	0.090
Sift	Benign	1.0	T
Sift4G	Benign	1.0	T
Polyphen		0.0	B
Vest4		0.066
MutPred		0.53		Gain of catalytic residue at S136 (P = 0);
MVP		0.061
MPC		0.023
ClinPred		0.092	T
GERP RS		-3.1
Varity_R		0.050
gMVP		0.045

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

Publications

LitVar

Other links and lift over

dbSNP: rs1478037094; hg19: chr12-11150078;