rs1554358639

chr7-94628206-A-Gchr7-94628206-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_003919.3(SGCE):c.386T>C(p.Ile129Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,458,624 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I129N) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: SGCE NM_003919.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.78

Genes affected

SGCE (HGNC:10808): (sarcoglycan epsilon) This gene encodes the epsilon member of the sarcoglycan family. Sarcoglycans are transmembrane proteins that are components of the dystrophin-glycoprotein complex, which link the actin cytoskeleton to the extracellular matrix. Unlike other family members which are predominantly expressed in striated muscle, the epsilon sarcoglycan is more broadly expressed. Mutations in this gene are associated with myoclonus-dystonia syndrome. This gene is imprinted, with preferential expression from the paternal allele. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. A pseudogene associated with this gene is located on chromosome 2. [provided by RefSeq, Oct 2016]

CASD1 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.965

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SGCE	NM_003919.3	c.386T>C	p.Ile129Thr	missense_variant	3/11	ENST00000648936.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SGCE	ENST00000648936.2	c.386T>C	p.Ile129Thr	missense_variant	3/11		NM_003919.3	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1458624 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 725676

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: 9.01e-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

Myoclonic dystonia 11 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 08, 2019

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has been observed to segregate with myoclonic dystonia in a family (PMID: 22026499). This variant is not present in population databases (ExAC no frequency). This sequence change replaces isoleucine with threonine at codon 129 of the SGCE protein (p.Ile129Thr). The isoleucine residue is highly conserved and there is a moderate physicochemical difference between isoleucine and threonine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.55
Cadd	Pathogenic	27
Dann	Uncertain	1.0
Eigen	Pathogenic	0.80
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D;D;.;D;D;D;D;D;D;D;D;D;D;D;D;D;T;D;.;D;D;D;D;D;D;D;D;.;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.57	D
MetaRNN	Pathogenic	0.97	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Uncertain	0.74	T
Polyphen		0.99, 0.98, 1.0	.;.;D;.;D;.;.;.;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.
Vest4		0.97, 0.98, 0.96, 0.96, 0.97
MutPred		0.84		.;.;.;.;.;Gain of disorder (P = 0.0353);.;.;.;.;.;.;.;.;Gain of disorder (P = 0.0353);Gain of disorder (P = 0.0353);.;.;.;.;Gain of disorder (P = 0.0353);.;.;.;.;.;.;Gain of disorder (P = 0.0353);Gain of disorder (P = 0.0353);.;.;.;Gain of disorder (P = 0.0353);Gain of disorder (P = 0.0353);.;.;
MVP		0.96
MPC		0.86
ClinPred		0.99	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.62
gMVP		0.90

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: rs1554358639; hg19: chr7-94257518;