rs774943243

Variant names:

• chr3-122284875-C-T
• rs774943243
• NM_000388.4:c.2921C>T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 1P and 2B. PP2 BP4 BP6

The NM_000388.4(CASR):​c.2921C>T​(p.Thr974Ile) variant causes a missense change. The variant allele was found at a frequency of 0.00000479 in 1,461,866 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T974S) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: CASR NM_000388.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 3.63
• Publications: 0 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=0.37927282).
• BP6: Variant 3-122284875-C-T is Benign according to our data. Variant chr3-122284875-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 573151.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000388.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CASR	NM_000388.4	MANE Select	c.2921C>T	p.Thr974Ile	missense	Exon 7 of 7	NP_000379.3
	CASR	NM_001178065.2		c.2951C>T	p.Thr984Ile	missense	Exon 7 of 7	NP_001171536.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CASR	ENST00000639785.2	TSL:1 MANE Select	c.2921C>T	p.Thr974Ile	missense	Exon 7 of 7	ENSP00000491584.2
	CASR	ENST00000498619.4	TSL:1	c.2951C>T	p.Thr984Ile	missense	Exon 7 of 7	ENSP00000420194.1
	CASR	ENST00000638421.1	TSL:5	c.2921C>T	p.Thr974Ile	missense	Exon 7 of 7	ENSP00000492190.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.0000239 AC: 6 AN: 251428 AF XY: 0.0000221

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000145

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461866 Hom.: 0 Cov.: 70 AF XY: 0.00000550 AC XY: 4 AN XY: 727236

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.000157 AC: 7 AN: 44724

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111990

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 33

ExAC AF: 0.0000247 AC: 3

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	1	-	Autosomal dominant hypocalcemia 1;C1809471:Familial hypocalciuric hypercalcemia (1)
-	-	1	Nephrolithiasis/nephrocalcinosis (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.47
BayesDel_addAF	Benign	0.0043	T
BayesDel_noAF	Uncertain	0.050
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.39	T
Eigen	Uncertain	0.30
Eigen_PC	Uncertain	0.43
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.91	D
M_CAP	Uncertain	0.16	D
MetaRNN	Benign	0.38	T
MetaSVM	Uncertain	0.30	D
MutationAssessor	Benign	1.8	L
PhyloP100		3.6
PrimateAI	Uncertain	0.67	T
PROVEAN	Benign	-1.0	N
REVEL	Uncertain	0.55
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0040	D
Polyphen		0.73	P
Vest4		0.46
MutPred		0.33		Loss of glycosylation at S980 (P = 0.0296)
MVP		0.95
MPC		1.7
ClinPred		0.31	T
GERP RS		5.8
Varity_R		0.35
gMVP		0.54
Mutation Taster		=88/12	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: rs774943243; hg19: chr3-122003722;