1-228211940-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_001386125.1(OBSCN):c.157G>T(p.Gly53Cys) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. G53G) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: OBSCN NM_001386125.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.78

Genes affected

OBSCN (HGNC:15719): (obscurin, cytoskeletal calmodulin and titin-interacting RhoGEF) The obscurin gene spans more than 150 kb, contains over 80 exons and encodes a protein of approximately 720 kDa. The encoded protein contains 68 Ig domains, 2 fibronectin domains, 1 calcium/calmodulin-binding domain, 1 RhoGEF domain with an associated PH domain, and 2 serine-threonine kinase domains. This protein belongs to the family of giant sacromeric signaling proteins that includes titin and nebulin, and may have a role in the organization of myofibrils during assembly and may mediate interactions between the sarcoplasmic reticulum and myofibrils. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008]

OBSCN-AS1 (HGNC:32047): (OBSCN antisense RNA 1)

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.767

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
OBSCN	NM_001386125.1	c.157G>T	p.Gly53Cys	missense_variant	2/116	ENST00000680850.1
OBSCN-AS1	NR_073155.1	n.234+1482C>A		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
OBSCN	ENST00000680850.1	c.157G>T	p.Gly53Cys	missense_variant	2/116		NM_001386125.1	P4
OBSCN-AS1	ENST00000295012.5	n.239+1482C>A		intron_variant, non_coding_transcript_variant		1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 72

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 05, 2023

The c.157G>T (p.G53C) alteration is located in exon 2 (coding exon 1) of the OBSCN gene. This alteration results from a G to T substitution at nucleotide position 157, causing the glycine (G) at amino acid position 53 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.42
BayesDel_addAF	Benign	-0.080	T
BayesDel_noAF	Benign	-0.35
Cadd	Benign	23
Dann	Uncertain	0.99
Eigen	Uncertain	0.45
Eigen_PC	Uncertain	0.31
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.64	T;T;T;.;.
M_CAP	Pathogenic	0.47	D
MetaRNN	Pathogenic	0.77	D;D;D;D;D
MetaSVM	Benign	-0.57	T
MutationAssessor	Uncertain	2.8	M;M;.;.;M
MutationTaster	Benign	0.98	D;D;D;D;D
PrimateAI	Benign	0.48	T
PROVEAN	Pathogenic	-4.7	D;D;D;.;.
REVEL	Uncertain	0.33
Sift	Benign	0.041	D;D;D;.;.
Sift4G	Pathogenic	0.0	D;D;D;D;.
Polyphen		1.0	D;D;.;.;D
Vest4		0.32
MutPred		0.63		Loss of disorder (P = 0.049);Loss of disorder (P = 0.049);Loss of disorder (P = 0.049);Loss of disorder (P = 0.049);Loss of disorder (P = 0.049);
MVP		0.71
MPC		2.2
ClinPred		0.98	D
GERP RS		3.9
Varity_R		0.84
gMVP		0.85

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr1-228399641;