1-160190754-G-A

Variant names:

• chr1-160190754-G-A
• rs905911175
• NM_001231.5:c.3G>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PVS1_Supporting PM2

The NM_001231.5(CASQ1):​c.3G>A​(p.Met1?) variant causes a start lost change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000658 in 152,080 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: CASQ1 NM_001231.5 start_lost
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.68
• Publications: 0 publications found

Genes affected

CASQ1 (HGNC:1512): (calsequestrin 1) This gene encodes the skeletal muscle specific member of the calsequestrin protein family. Calsequestrin functions as a luminal sarcoplasmic reticulum calcium sensor in both cardiac and skeletal muscle cells. This protein, also known as calmitine, functions as a calcium regulator in the mitochondria of skeletal muscle. This protein is absent in patients with Duchenne and Becker types of muscular dystrophy. [provided by RefSeq, Jun 2013]

CASQ1 Gene-Disease associations (from GenCC):

• myopathy due to calsequestrin and SERCA1 protein overload

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
• tubular aggregate myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000304031 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PVS1: Start lost variant, no pathogenic variants between lost start and next in-frame start position. Next in-frame start position is after 7 codons. Genomic position: 160190770. Lost 0.016 part of the original CDS.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CASQ1	NM_001231.5	c.3G>A	p.Met1?	start_lost	Exon 1 of 11	ENST00000368078.8	NP_001222.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CASQ1	ENST00000368078.8	c.3G>A	p.Met1?	start_lost	Exon 1 of 11	1	NM_001231.5	ENSP00000357057.3

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152080 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

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 Cov.: 31

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152080 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74266

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41412

American (AMR) AF: 0.0000655 AC: 1 AN: 15278

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4822

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10598

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68006

Other (OTH) AF: 0.00 AC: 0 AN: 2084

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Oct 05, 2022

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. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. This variant has not been reported in the literature in individuals affected with CASQ1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects the initiator methionine of the CASQ1 mRNA. The next in-frame methionine is located at codon 7. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.038	T
BayesDel_noAF	Benign	-0.29
CADD	Benign	15
DANN	Benign	0.97
DEOGEN2	Benign	0.14	T
Eigen	Benign	-0.45
Eigen_PC	Benign	-0.41
FATHMM_MKL	Benign	0.10	N
LIST_S2	Uncertain	0.90	D
M_CAP	Benign	0.074	D
MetaRNN	Pathogenic	0.84	D
MetaSVM	Benign	-0.83	T
PhyloP100		2.7
PROVEAN	Benign	-0.39	N
REVEL	Benign	0.26
Sift	Benign	0.041	D
Sift4G	Pathogenic	0.0	D
Polyphen		0.0010	B
Vest4		0.30
MutPred		0.99		Loss of phosphorylation at S2 (P = 0.095);
MVP		0.54
ClinPred		0.26	T
GERP RS		4.1
PromoterAI		-0.018	Neutral
Varity_R		0.29
gMVP		0.66
Mutation Taster		=134/66	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: rs905911175; hg19: chr1-160160544;