NM_000388.4:c.1175G>A

Variant names:

• chr3-122262210-G-A
• rs1287075426
• NM_000388.4:c.1175G>A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 1P and 0B. PP2

The NM_000388.4(CASR):​c.1175G>A​(p.Arg392Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000547 in 1,461,768 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: CASR NM_000388.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 8.15

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 Uncertain_significance. Variant got 1 ACMG points.

• 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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CASR	NM_000388.4	c.1175G>A	p.Arg392Gln	missense_variant	Exon 4 of 7	ENST00000639785.2	NP_000379.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CASR	ENST00000639785.2	c.1175G>A	p.Arg392Gln	missense_variant	Exon 4 of 7	1	NM_000388.4	ENSP00000491584.2
CASR	ENST00000498619.4	c.1175G>A	p.Arg392Gln	missense_variant	Exon 4 of 7	1		ENSP00000420194.1
CASR	ENST00000638421.1	c.1175G>A	p.Arg392Gln	missense_variant	Exon 4 of 7	5		ENSP00000492190.1
CASR	ENST00000490131.7	c.1175G>A	p.Arg392Gln	missense_variant	Exon 3 of 5	5		ENSP00000418685.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000547 AC: 8 AN: 1461768 Hom.: 0 Cov.: 33 AF XY: 0.00000550 AC XY: 4 AN XY: 727206

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000630

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000624 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Nephrolithiasis/nephrocalcinosis Uncertain:1

Apr 22, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R392Q variant (also known as c.1175G>A), located in coding exon 3 of the CASR gene, results from a G to A substitution at nucleotide position 1175. The arginine at codon 392 is replaced by glutamine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Autosomal dominant hypocalcemia 1;C1809471:Familial hypocalciuric hypercalcemia Uncertain:1

Jul 30, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 392 of the CASR protein (p.Arg392Gln). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CASR-related conditions. ClinVar contains an entry for this variant (Variation ID: 532614). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. 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. -

Autosomal dominant hypocalcemia 1;C0342637:Familial hypocalciuric hypercalcemia 1;C1832615:Neonatal severe primary hyperparathyroidism;C2752062:Epilepsy, idiopathic generalized, susceptibility to, 8 Uncertain:1

Apr 23, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.24
CADD	Benign	23
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.38	T;T;.;.
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.90	.;D;D;D
M_CAP	Uncertain	0.16	D
MetaRNN	Uncertain	0.71	D;D;D;D
MetaSVM	Uncertain	0.27	D
MutationAssessor	Benign	1.2	L;L;L;.
PrimateAI	Uncertain	0.55	T
PROVEAN	Benign	-0.94	.;.;N;N
REVEL	Pathogenic	0.68
Sift	Uncertain	0.026	.;.;D;D
Sift4G	Benign	0.084	.;.;T;T
Polyphen		1.0	D;D;.;.
Vest4		0.69, 0.69
MutPred		0.51		Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);Loss of helix (P = 0.0376);
MVP		0.96
MPC		1.2
ClinPred		0.96	D
GERP RS		5.9
Varity_R		0.62
gMVP		0.79

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

Publications

LitVar

Other links and lift over

dbSNP: rs1287075426; hg19: chr3-121981057; COSMIC: COSV56139780; COSMIC: COSV56139780;