rs1060499782

Variant names:

• chr2-232535129-GGA-G
• rs1060499782
• NM_000751.3:c.1374_1375delGA

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1_Strong PM2 PP3_Moderate PP5_Moderate

The NM_000751.3(CHRND):​c.1374_1375delGA​(p.Lys459fs) variant causes a frameshift, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,238 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: CHRND NM_000751.3 frameshift, splice_region
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.95
• Publications: 0 publications found

Genes affected

CHRND (HGNC:1965): (cholinergic receptor nicotinic delta subunit) The acetylcholine receptor of muscle has 5 subunits of 4 different types: 2 alpha and 1 each of beta, gamma and delta subunits. After acetylcholine binding, the receptor undergoes an extensive conformation change that affects all subunits and leads to opening of an ion-conducting channel across the plasma membrane. Defects in this gene are a cause of multiple pterygium syndrome lethal type (MUPSL), congenital myasthenic syndrome slow-channel type (SCCMS), and congenital myasthenic syndrome fast-channel type (FCCMS). Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2015]

CHRND Gene-Disease associations (from GenCC):

• congenital myasthenic syndrome 3A

  Inheritance: AD Classification: STRONG Submitted by: PanelApp Australia, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• congenital myasthenic syndrome 3B

  Inheritance: AR Classification: STRONG Submitted by: PanelApp Australia, Genomics England PanelApp
• congenital myasthenic syndrome 3C

  Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• lethal multiple pterygium syndrome

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)
• postsynaptic congenital myasthenic syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.116 CDS is truncated, and there are 3 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 2-232535129-GGA-G is Pathogenic according to our data. Variant chr2-232535129-GGA-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 402225.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000751.3. 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
	CHRND	NM_000751.3	MANE Select	c.1374_1375delGA	p.Lys459fs	frameshift splice_region	Exon 12 of 12	NP_000742.1
	CHRND	NM_001256657.2		c.1329_1330delGA	p.Lys444fs	frameshift splice_region	Exon 11 of 11	NP_001243586.1
	CHRND	NM_001311196.2		c.1071_1072delGA	p.Lys358fs	frameshift splice_region	Exon 12 of 12	NP_001298125.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHRND	ENST00000258385.8	TSL:1 MANE Select	c.1374_1375delGA	p.Lys459fs	frameshift splice_region	Exon 12 of 12	ENSP00000258385.3
	CHRND	ENST00000543200.5	TSL:2	c.1329_1330delGA	p.Lys444fs	frameshift splice_region	Exon 11 of 11	ENSP00000438380.1
	CHRND	ENST00000955151.1		c.1173_1174delGA	p.Lys392fs	frameshift splice_region	Exon 11 of 11	ENSP00000625210.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152238 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152238 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74384

⚠️ 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: 41466

American (AMR) AF: 0.00 AC: 0 AN: 15292

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3466

East Asian (EAS) AF: 0.00 AC: 0 AN: 5200

South Asian (SAS) AF: 0.00 AC: 0 AN: 4836

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10632

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

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68030

Other (OTH) AF: 0.00 AC: 0 AN: 2090

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions as Germline

Significance: Likely pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Lethal multiple pterygium syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		10
Mutation Taster		=19/181	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		1.0		Position offset: 3
DS_AL_spliceai		1.0		Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1060499782; hg19: chr2-233399839;