8-120632620-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_021021.4(SNTB1):c.820C>T(p.His274Tyr) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,866 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SNTB1 NM_021021.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.06

Genes affected

SNTB1 (HGNC:11168): (syntrophin beta 1) Dystrophin is a large, rod-like cytoskeletal protein found at the inner surface of muscle fibers. Dystrophin is missing in Duchenne Muscular Dystrophy patients and is present in reduced amounts in Becker Muscular Dystrophy patients. The protein encoded by this gene is a peripheral membrane protein found associated with dystrophin and dystrophin-related proteins. This gene is a member of the syntrophin gene family, which contains at least two other structurally-related genes. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SNTB1	NM_021021.4	c.820C>T	p.His274Tyr	missense_variant	3/7	ENST00000517992.2
SNTB1	XM_011517239.3	c.820C>T	p.His274Tyr	missense_variant	3/5
SNTB1	XM_047422126.1	c.241C>T	p.His81Tyr	missense_variant	3/7
SNTB1	XM_047422127.1	c.241C>T	p.His81Tyr	missense_variant	3/7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SNTB1	ENST00000517992.2	c.820C>T	p.His274Tyr	missense_variant	3/7	1	NM_021021.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461866 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727232

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

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

Jul 12, 2023

The c.820C>T (p.H274Y) alteration is located in exon 3 (coding exon 3) of the SNTB1 gene. This alteration results from a C to T substitution at nucleotide position 820, causing the histidine (H) at amino acid position 274 to be replaced by a tyrosine (Y). 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	Benign	0.14
BayesDel_addAF	Uncertain	0.089	D
BayesDel_noAF	Benign	-0.11
Cadd	Benign	22
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.47	T;T
Eigen	Uncertain	0.27
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Pathogenic	0.97	D
M_CAP	Benign	0.031	D
MetaRNN	Uncertain	0.55	D;D
MetaSVM	Benign	-0.91	T
MutationAssessor	Benign	1.9	L;L
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.76	T
PROVEAN	Uncertain	-3.2	D;D
REVEL	Benign	0.24
Sift	Benign	0.032	D;D
Sift4G	Benign	0.46	T;T
Polyphen		0.14	B;B
Vest4		0.83
MutPred		0.42		Gain of phosphorylation at H274 (P = 0.032);Gain of phosphorylation at H274 (P = 0.032);
MVP		0.20
ClinPred		0.92	D
GERP RS		6.0
Varity_R		0.32
gMVP		0.70

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: chr8-121644860;