rs4987051

Variant names:

• chr3-122284805-C-A
• rs4987051
• NM_000388.4:c.2851C>A

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 1P and 2B. PP2 BP4_Moderate

The NM_000388.4(CASR):​c.2851C>A​(p.Pro951Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,614,144 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign 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. P951R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: CASR NM_000388.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.29
• Publications: 4 publications found

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]

CASR Gene-Disease associations (from GenCC):

• autosomal dominant hypocalcemia 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Illumina, ClinGen, Labcorp Genetics (formerly Invitae)
• familial hypocalciuric hypercalcemia 1

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Illumina, Orphanet, Genomics England PanelApp
• neonatal severe primary hyperparathyroidism

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, Labcorp Genetics (formerly Invitae)
• autosomal dominant hypocalcemia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• epilepsy, idiopathic generalized, susceptibility to, 8

  Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
• epilepsy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Likely_benign. The variant received -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 neonatal severe primary hyperparathyroidism, autosomal dominant hypocalcemia 1, familial hypocalciuric hypercalcemia 1, epilepsy, autosomal dominant hypocalcemia, epilepsy, idiopathic generalized, susceptibility to, 8.
• BP4: Computational evidence support a benign effect (MetaRNN=0.10520524).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CASR	NM_000388.4	c.2851C>A	p.Pro951Thr	missense_variant	Exon 7 of 7	ENST00000639785.2	NP_000379.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CASR	ENST00000639785.2	c.2851C>A	p.Pro951Thr	missense_variant	Exon 7 of 7	1	NM_000388.4	ENSP00000491584.2
CASR	ENST00000498619.4	c.2881C>A	p.Pro961Thr	missense_variant	Exon 7 of 7	1		ENSP00000420194.1
CASR	ENST00000638421.1	c.2851C>A	p.Pro951Thr	missense_variant	Exon 7 of 7	5		ENSP00000492190.1
CASR	ENST00000490131.7	c.2620C>A	p.Pro874Thr	missense_variant	Exon 5 of 5	5		ENSP00000418685.2

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152140 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000483

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461886 Hom.: 0 Cov.: 70 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

African (AFR) AF: 0.0000597 AC: 2 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112010

Other (OTH) AF: 0.0000331 AC: 2 AN: 60396

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152258 Hom.: 0 Cov.: 33 AF XY: 0.0000537 AC XY: 4 AN XY: 74450

African (AFR) AF: 0.0000963 AC: 4 AN: 41542

American (AMR) AF: 0.00 AC: 0 AN: 15298

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5176

South Asian (SAS) AF: 0.00 AC: 0 AN: 4826

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10614

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68012

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Mar 26, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. This sequence change replaces proline, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 951 of the CASR protein (p.Pro951Thr). 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: 532581). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.070
BayesDel_addAF	Benign	-0.077	T
BayesDel_noAF	Benign	-0.35
CADD	Benign	9.4
DANN	Benign	0.72
DEOGEN2	Benign	0.27	T;T;.;.
Eigen	Benign	-0.83
Eigen_PC	Benign	-0.74
FATHMM_MKL	Benign	0.41	N
LIST_S2	Benign	0.37	.;T;T;T
M_CAP	Benign	0.073	D
MetaRNN	Benign	0.11	T;T;T;T
MetaSVM	Benign	-0.72	T
MutationAssessor	Benign	0.69	N;N;.;.
PhyloP100		3.3
PrimateAI	Benign	0.30	T
PROVEAN	Benign	-0.38	.;.;N;.
REVEL	Benign	0.22
Sift	Benign	0.19	.;.;T;.
Sift4G	Uncertain	0.017	.;.;D;.
Polyphen		0.0	B;B;.;.
Vest4		0.10
MutPred		0.13		.;.;Loss of glycosylation at P957 (P = 0.0105);.;
MVP		0.76
MPC		0.68
ClinPred		0.16	T
GERP RS		4.3
Varity_R		0.063
gMVP		0.35
Mutation Taster		=97/3	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: rs4987051; hg19: chr3-122003652;