3-122284347-C-T

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1PM2PP2PP3_StrongPP5_Very_Strong

The NM_000388.4(CASR):​c.2393C>T​(p.Pro798Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,184 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P798S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

CASR
NM_000388.4 missense

Scores

15
3

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 7.91

Publications

7 publications found
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 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 17 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 21 uncertain 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 neonatal severe primary hyperparathyroidism, autosomal dominant hypocalcemia 1, familial hypocalciuric hypercalcemia 1, epilepsy, autosomal dominant hypocalcemia, epilepsy, idiopathic generalized, susceptibility to, 8.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.98
PP5
Variant 3-122284347-C-T is Pathogenic according to our data. Variant chr3-122284347-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 410346.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CASRNM_000388.4 linkc.2393C>T p.Pro798Leu missense_variant Exon 7 of 7 ENST00000639785.2 NP_000379.3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CASRENST00000639785.2 linkc.2393C>T p.Pro798Leu missense_variant Exon 7 of 7 1 NM_000388.4 ENSP00000491584.2
CASRENST00000498619.4 linkc.2423C>T p.Pro808Leu missense_variant Exon 7 of 7 1 ENSP00000420194.1
CASRENST00000638421.1 linkc.2393C>T p.Pro798Leu missense_variant Exon 7 of 7 5 ENSP00000492190.1
CASRENST00000490131.7 linkc.2162C>T p.Pro721Leu missense_variant Exon 5 of 5 5 ENSP00000418685.2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152184
Hom.:
0
Cov.:
33
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
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
1461772
Hom.:
0
Cov.:
70
AF XY:
0.00
AC XY:
0
AN XY:
727194
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
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:
53304
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112006
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152184
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74332
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000241
AC:
1
AN:
41452
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3464
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.225
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Mar 04, 2025
Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Apr 21, 2023
Athena Diagnostics
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In some published literature, this variant is referred to as c.2423C>T p.(Pro808Leu). This variant has been identified in multiple unrelated individuals with clinical features of hypocalciuric hypercalcemia. At least one other missense variant at this codon is considered to be pathogenic or likely pathogenic, suggesting this variant may also cause disease. This variant has not been reported in large, multi-ethnic general populations (http://gnomad.broadinstitute.org). Computational tools predict that this variant is damaging.

Autosomal dominant hypocalcemia 1;C1809471:Familial hypocalciuric hypercalcemia Pathogenic:1
Dec 16, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 798 of the CASR protein (p.Pro798Leu). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with familial hypocalciuric hypercalcemia (PMID: 15963484, 22422767, 31672324; Invitae). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 410346). 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. This variant disrupts the p.Pro798 amino acid residue in CASR. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 15963484, 19389809). 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.

Familial hypocalciuric hypercalcemia Pathogenic:1
Jun 04, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: CASR c.2393C>T (p.Pro798Leu) results in a non-conservative amino acid change located in the GPCR family 3, C-terminal domain (IPR017978) of the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function all suggest that this variant is likely to be disruptive. The variant was absent in 251304 control chromosomes. c.2393C>T has been observed in multiple individuals affected with Familial Hypocalciuric Hypercalcemia and/or autosomal dominant Familial Hyperparathyroidism (e.g. Hannan_2012, Hureaux_2019, Gorvin_2019, Mariathasan_2020, Mazarico-Altisent_2023). These data indicate that the variant is very likely to be associated with disease. A different variant affecting the same codon has been classified as pathogenic by our lab (c.2392C>A, p.Pro798Thr), supporting the critical relevance of codon 798 to CASR protein function. The following publications have been ascertained in the context of this evaluation (PMID: 31189130, 22422767, 31672324, 32430905, 37810884). ClinVar contains an entry for this variant (Variation ID: 410346). 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
0.98
BayesDel_addAF
Pathogenic
0.46
D
BayesDel_noAF
Pathogenic
0.43
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.92
D;D;.;.
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
1.0
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.0
.;D;D;D
M_CAP
Pathogenic
0.56
D
MetaRNN
Pathogenic
0.98
D;D;D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Pathogenic
3.2
M;M;.;.
PhyloP100
7.9
PrimateAI
Pathogenic
0.91
D
PROVEAN
Benign
0.0
.;.;D;.
REVEL
Benign
0.0
Sift
Pathogenic
0.0
.;.;D;.
Sift4G
Pathogenic
0.0
.;.;D;.
Vest4
0.0
ClinPred
1.0
D
GERP RS
6.0
Varity_R
0.87
gMVP
0.94
Mutation Taster
=1/99
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs1060502856; hg19: chr3-122003194; COSMIC: COSV56135853; API