2-232527436-G-C

Position:

• chr2-232527436-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000751.3(CHRND):​c.234G>C​(p.Trp78Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,234 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.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CHRND NM_000751.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 8.98

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a topological_domain Extracellular (size 223) in uniprot entity ACHD_HUMAN there are 10 pathogenic changes around while only 2 benign (83%) in NM_000751.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.993

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHRND	NM_000751.3	c.234G>C	p.Trp78Cys	missense_variant	3/12	ENST00000258385.8	NP_000742.1
CHRND	NM_001311196.2	c.-38G>C		5_prime_UTR_variant	3/12		NP_001298125.1
CHRND	NM_001311195.2	c.-38G>C		5_prime_UTR_variant	3/10		NP_001298124.1
CHRND	NM_001256657.2	c.198+762G>C		intron_variant			NP_001243586.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHRND	ENST00000258385.8	c.234G>C	p.Trp78Cys	missense_variant	3/12	1	NM_000751.3	ENSP00000258385.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461234 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726966

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	32
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.85	D
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.64	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.86	D
MutationAssessor	Pathogenic	4.4	H
PrimateAI	Uncertain	0.78	T
PROVEAN	Pathogenic	-11	D
REVEL	Pathogenic	0.92
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.95
MutPred		0.87		Loss of catalytic residue at W78 (P = 0.0168);
MVP		1.0
MPC		1.1
ClinPred		1.0	D
GERP RS		4.0
Varity_R		0.98
gMVP		0.91

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.11		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: rs121909505; hg19: chr2-233392146;