3-122254374-G-T

Variant names:

• chr3-122254374-G-T
• rs121909265
• NM_000388.4:c.185G>T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3 PP5

The NM_000388.4(CASR):​c.185G>T​(p.Arg62Met) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CASR NM_000388.4 missense, splice_region
• Scores: Splicing: ADA: 0.9997
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 9.92

Genes affected

CASR (HGNC:1514): (calcium sensing receptor) The protein encoded by this gene is a plasma membrane G protein-coupled receptor that senses small changes in circulating calcium concentration. The encoded protein couples this information to intracellular signaling pathways that modify parathyroid hormone secretion or renal cation handling, and thus this protein plays an essential role in maintaining mineral ion homeostasis. Mutations in this gene are a cause of familial hypocalciuric hypercalcemia, neonatal severe hyperparathyroidism, and autosomal dominant hypocalcemia. [provided by RefSeq, Aug 2017]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a region_of_interest Ligand-binding 1 (LB1) (size 166) in uniprot entity CASR_HUMAN there are 70 pathogenic changes around while only 0 benign (100%) in NM_000388.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the CASR gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 114 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: 3.1237 (above the threshold of 3.09). Trascript score misZ: 4.8257 (above the threshold of 3.09). GenCC associations: The gene is linked to epilepsy, autosomal dominant hypocalcemia, familial hypocalciuric hypercalcemia 1, epilepsy, idiopathic generalized, susceptibility to, 8, neonatal severe primary hyperparathyroidism, autosomal dominant hypocalcemia 1.
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. Scorers claiming Uncertain: max_spliceai. No scorers claiming Benign.
• PP5: Variant 3-122254374-G-T is Pathogenic according to our data. Variant chr3-122254374-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 8334.Status of the report is no_assertion_criteria_provided, 0 stars. Variant chr3-122254374-G-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CASR	NM_000388.4	c.185G>T	p.Arg62Met	missense_variant, splice_region_variant	Exon 2 of 7	ENST00000639785.2	NP_000379.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CASR	ENST00000639785.2	c.185G>T	p.Arg62Met	missense_variant, splice_region_variant	Exon 2 of 7	1	NM_000388.4	ENSP00000491584.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Familial hypocalciuric hypercalcemia 1 Pathogenic:1

May 01, 1995

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.85
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	31
DANN	Benign	0.96
DEOGEN2	Uncertain	0.70	D;D;.;.
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.82	.;T;T;T
M_CAP	Uncertain	0.24	D
MetaRNN	Pathogenic	0.80	D;D;D;D
MetaSVM	Uncertain	0.78	D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-2.4	.;.;N;N
REVEL	Pathogenic	0.80
Sift	Benign	0.055	.;.;T;D
Sift4G	Benign	0.13	.;.;T;T
Polyphen		1.0	D;D;.;.
Vest4		0.77, 0.77
MutPred		0.58		Gain of catalytic residue at V58 (P = 0.0148);Gain of catalytic residue at V58 (P = 0.0148);Gain of catalytic residue at V58 (P = 0.0148);Gain of catalytic residue at V58 (P = 0.0148);
MVP		0.99
MPC		1.7
ClinPred		0.97	D
GERP RS		5.4
Varity_R		0.62
gMVP		0.91

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.98
SpliceAI score (max)		0.47		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.47		Position offset: 0

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs121909265; hg19: chr3-121973221;