chr5-156344554-C-G

Variant names:

• chr5-156344554-C-G
• rs397517923
• NM_000337.6:c.69C>G

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PVS1

The NM_000337.6(SGCD):​c.69C>G​(p.Tyr23*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000548 in 1,459,756 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. Y23Y) has been classified as Likely benign. The gene SGCD is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: SGCD NM_000337.6 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.33
• Publications: 0 publications found

Genes affected

SGCD (HGNC:10807): (sarcoglycan delta) The protein encoded by this gene is one of the four known components of the sarcoglycan complex, which is a subcomplex of the dystrophin-glycoprotein complex (DGC). DGC forms a link between the F-actin cytoskeleton and the extracellular matrix. This protein is expressed most abundantly in skeletal and cardiac muscle. Mutations in this gene have been associated with autosomal recessive limb-girdle muscular dystrophy and dilated cardiomyopathy. Alternatively spliced transcript variants encoding distinct isoforms have been observed for this gene. [provided by RefSeq, Jul 2008]

SGCD Gene-Disease associations (from GenCC):

• autosomal recessive limb-girdle muscular dystrophy

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: ClinGen, PanelApp Australia
• autosomal recessive limb-girdle muscular dystrophy type 2F

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, Orphanet
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• dilated cardiomyopathy

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• dilated cardiomyopathy 1L

  Inheritance: AD Classification: NO_KNOWN Submitted by: Ambry Genetics

LOC124901120 (HGNC:):

ACMG classification

Specifications for SGCD are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 36 pathogenic variants in the truncated region.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000337.6. 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
	SGCD	NM_000337.6	MANE Select	c.69C>G	p.Tyr23*	stop_gained	Exon 3 of 9	NP_000328.2
	SGCD	NM_001128209.2		c.66C>G	p.Tyr22*	stop_gained	Exon 2 of 8	NP_001121681.1	Q92629-1
	SGCD	NM_172244.3		c.69C>G	p.Tyr23*	stop_gained	Exon 3 of 8	NP_758447.1	Q92629-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SGCD	ENST00000337851.9	TSL:1 MANE Select	c.69C>G	p.Tyr23*	stop_gained	Exon 3 of 9	ENSP00000338343.4	Q92629-2
	SGCD	ENST00000435422.7	TSL:1	c.66C>G	p.Tyr22*	stop_gained	Exon 2 of 8	ENSP00000403003.2	Q92629-1
	SGCD	ENST00000959784.1		c.69C>G	p.Tyr23*	stop_gained	Exon 3 of 10	ENSP00000629843.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000548 AC: 8 AN: 1459756 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 726062

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

African (AFR) AF: 0.00 AC: 0 AN: 33408

American (AMR) AF: 0.00 AC: 0 AN: 44576

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26094

East Asian (EAS) AF: 0.00 AC: 0 AN: 39572

South Asian (SAS) AF: 0.00 AC: 0 AN: 85836

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53394

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00000720 AC: 8 AN: 1110806

Other (OTH) AF: 0.00 AC: 0 AN: 60306

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.00000241541), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.63
CADD	Pathogenic	39
DANN	Uncertain	1.0
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		3.3
Vest4		0.80
GERP RS		5.6
Mutation Taster		=0/200	disease causing (fs/PTC)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs397517923; hg19: chr5-155771564;