rs767363250

Variant summary

Our verdict is Pathogenic. Variant got 17 ACMG points: 17P and 0B. PM1PM5PP2PP3_StrongPP5_Very_Strong

The NM_000388.4(CASR):c.2038C>T(p.Arg680Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,613,656 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R680H) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

CASR
NM_000388.4 missense

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 3.14

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 17 ACMG points.

PM1

In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 12 uncertain in NM_000388.4

PM5

Other missense variant is known to change same aminoacid residue: Variant chr3-122283993-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 237763.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

PP2

Missense variant where missense usually causes diseases, CASR

PP3

MetaRNN computational evidence supports a deleterious effect, 0.989

PP5

Variant 3-122283992-C-T is Pathogenic according to our data. Variant chr3-122283992-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 410347.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-122283992-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CASR	NM_000388.4 linkuse as main transcript	c.2038C>T	p.Arg680Cys	missense_variant	7/7	ENST00000639785.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CASR	ENST00000639785.2 linkuse as main transcript	c.2038C>T	p.Arg680Cys	missense_variant	7/7	1	NM_000388.4	P1	P41180-1
CASR	ENST00000498619.4 linkuse as main transcript	c.2068C>T	p.Arg690Cys	missense_variant	7/7	1			P41180-2
CASR	ENST00000638421.1 linkuse as main transcript	c.2038C>T	p.Arg680Cys	missense_variant	7/7	5		P1	P41180-1
CASR	ENST00000490131.7 linkuse as main transcript	c.1807C>T	p.Arg603Cys	missense_variant	5/5	5

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152172

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251154

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135762

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000684

AC:

AN:

1461484

Hom.:

Cov.:

AF XY:

0.00000825

AC XY:

AN XY:

727026

show subpopulations

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:

0.00000720

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152172

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74340

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Autosomal dominant hypocalcemia 1;C1809471:Familial hypocalciuric hypercalcemia

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Nov 13, 2023

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 680 of the CASR protein (p.Arg680Cys). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This missense change has been observed in individual(s) with familial hypocalciuric hypercalcemia and/or neonatal severe hyperparathyroidism (PMID: 8675635, 15241688, 32347971, 32386559). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 410347). 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 disruptive. Experimental studies have shown that this missense change affects CASR function (PMID: 8878438, 17284438, 19389809, 22798347, 23372019, 32386559). This variant disrupts the p.Arg680 amino acid residue in CASR. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 19179454, 22798347, 23372019, 26646938, 26963950, 27666534, 32347971; Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Athena Diagnostics

Jan 27, 2022

The frequency of this variant in the general population is consistent with pathogenicity (http://gnomad.broadinstitute.org). This variant appears to be associated with disease in at least one family. At least one other missense variant at this codon is considered to be pathogenic or likely pathogenic, suggesting this variant may also cause disease. Assessment of experimental evidence suggests this variant results in abnormal protein function. This variant caused significant alterations in calcium potency and/or efficacy (PMID: 8878438, 22798347, 17284438). Computational tools predict that this variant is damaging. -

Familial hypocalciuric hypercalcemia

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Oct 20, 2022

Variant summary: CASR c.2038C>T (p.Arg680Cys) results in a non-conservative amino acid change located in the GPCR family 3, C-terminal domain (IPR017978) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251154 control chromosomes. c.2038C>T has been widely reported in the literature in individuals affected with features of Familial Hypocalciuric Hypercalcemia/Familial benign hypercalcemia (example, Pearce_1995, Mouly_2020). These data indicate that the variant is likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function (Pearce_1996). The most pronounced variant effect results in lack of responsiveness to gadolinium or calcium ions (<10% of normal activity) and severely reduced N-linked glycosylation despite normal receptor expression on the cell membrane. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.79

BayesDel_addAF

Pathogenic

0.41

BayesDel_noAF

Pathogenic

0.35

Cadd

Pathogenic

Dann

Pathogenic

1.0

DEOGEN2

Pathogenic

0.90

D;D;.;.

Eigen

Pathogenic

0.88

Eigen_PC

Pathogenic

0.81

FATHMM_MKL

Uncertain

0.96

M_CAP

Pathogenic

0.47

MetaRNN

Pathogenic

0.99

D;D;D;D

MetaSVM

Pathogenic

0.97

MutationAssessor

Pathogenic

3.0

M;M;.;.

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Pathogenic

0.83

Polyphen

1.0

D;D;.;.

Vest4

0.96

MutPred

0.96

.;.;Loss of sheet (P = 0.0817);.;

MVP

0.98

MPC

1.9

ClinPred

0.99

GERP RS

5.1

Varity_R

0.61

gMVP

0.93

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over