chr3-122284964-A-T

Position:

• chr3-122284964-A-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 5P and 2B. PM1 PM2 PP2 BP4_Moderate

The NM_000388.4(CASR):​c.3010A>T​(p.Ser1004Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 16/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: CASR NM_000388.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.35

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 3 ACMG points.

• PM1: In a topological_domain Cytoplasmic (size 215) in uniprot entity CASR_HUMAN there are 14 pathogenic changes around while only 2 benign (88%) in NM_000388.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), CASR. . Gene score misZ: 3.1237 (greater than the threshold 3.09). Trascript score misZ: 4.8257 (greater than threshold 3.09). The gene has 114 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. GenCC has associacion of the gene with epilepsy, autosomal dominant hypocalcemia, familial hypocalciuric hypercalcemia 1, epilepsy, idiopathic generalized, susceptibility to, 8, neonatal severe primary hyperparathyroidism, autosomal dominant hypocalcemia 1.
• BP4: Computational evidence support a benign effect (MetaRNN=0.08831799).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CASR	NM_000388.4	c.3010A>T	p.Ser1004Cys	missense_variant	7/7	ENST00000639785.2	NP_000379.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CASR	ENST00000639785.2	c.3010A>T	p.Ser1004Cys	missense_variant	7/7	1	NM_000388.4	ENSP00000491584.2
CASR	ENST00000498619.4	c.3040A>T	p.Ser1014Cys	missense_variant	7/7	1		ENSP00000420194.1
CASR	ENST00000638421.1	c.3010A>T	p.Ser1004Cys	missense_variant	7/7	5		ENSP00000492190.1
CASR	ENST00000490131.7	c.2779A>T	p.Ser927Cys	missense_variant	5/5	5		ENSP00000418685.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 70

GnomAD4 genome Cov.: 33

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 27, 2021

Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). 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 variant has not been reported in the literature in individuals with CASR-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces serine with cysteine at codon 1004 of the CASR protein (p.Ser1004Cys). The serine residue is weakly conserved and there is a moderate physicochemical difference between serine and cysteine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Benign	-0.054	T
BayesDel_noAF	Benign	-0.31
CADD	Benign	17
DANN	Benign	0.86
DEOGEN2	Benign	0.31	T;T;.;.
Eigen	Benign	-0.69
Eigen_PC	Benign	-0.67
FATHMM_MKL	Benign	0.56	D
LIST_S2	Benign	0.82	.;T;T;T
M_CAP	Benign	0.069	D
MetaRNN	Benign	0.088	T;T;T;T
MetaSVM	Benign	-0.57	T
MutationAssessor	Benign	0.0	N;N;.;.
PrimateAI	Benign	0.25	T
PROVEAN	Benign	-0.79	.;.;N;.
REVEL	Benign	0.20
Sift	Uncertain	0.0070	.;.;D;.
Sift4G	Uncertain	0.022	.;.;D;.
Polyphen		0.12	B;B;.;.
Vest4		0.098
MutPred		0.15		.;.;Loss of relative solvent accessibility (P = 0.008);.;
MVP		0.85
MPC		0.82
ClinPred		0.10	T
GERP RS		0.49
Varity_R		0.096
gMVP		0.19

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: rs780255825; hg19: chr3-122003811;