rs121909509

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PP3_Strong

The NM_000751.3(CHRND):c.236T>A(p.Ile79Lys) variant causes a missense change. The variant allele was found at a frequency of 0.00000496 in 1,613,168 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. I79T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000048 ( 0 hom. )

Consequence

CHRND
NM_000751.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter P:1U:1

Conservation

PhyloP100: 7.19

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.989

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
CHRND	NM_000751.3 linkuse as main transcript	c.236T>A	p.Ile79Lys	missense_variant	3/12	ENST00000258385.8
CHRND	NM_001311195.2 linkuse as main transcript	c.-36T>A		5_prime_UTR_variant	3/10
CHRND	NM_001311196.2 linkuse as main transcript	c.-36T>A		5_prime_UTR_variant	3/12
CHRND	NM_001256657.2 linkuse as main transcript	c.198+764T>A		intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CHRND	ENST00000258385.8 linkuse as main transcript	c.236T>A	p.Ile79Lys	missense_variant	3/12	1	NM_000751.3	P1	Q07001-1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

152002

Hom.:

Cov.:

show subpopulations

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

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251286

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135834

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000479

AC:

AN:

1461166

Hom.:

Cov.:

AF XY:

0.00000688

AC XY:

AN XY:

726946

show subpopulations

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:

0.00000450

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.00000658

AC:

AN:

152002

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74244

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Congenital myasthenic syndrome 3B

Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

May 01, 2008

- -

Lethal multiple pterygium syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 17, 2024

This sequence change replaces isoleucine, which is neutral and non-polar, with lysine, which is basic and polar, at codon 79 of the CHRND protein (p.Ile79Lys). This variant is present in population databases (rs121909509, gnomAD 0.002%). This missense change has been observed in individual(s) with clinical features of autosomal recessive CHRND-related conditions (PMID: 18398509, 29399782). This variant is also known as I58K. ClinVar contains an entry for this variant (Variation ID: 18365). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt CHRND protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects CHRND function (PMID: 18398509). 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.89

BayesDel_addAF

Pathogenic

0.45

BayesDel_noAF

Pathogenic

0.41

Cadd

Pathogenic

Dann

Benign

0.96

DEOGEN2

Uncertain

0.75

Eigen

Uncertain

0.36

Eigen_PC

Uncertain

0.38

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.88

M_CAP

Pathogenic

0.47

MetaRNN

Pathogenic

0.99

MetaSVM

Uncertain

0.59

MutationAssessor

Pathogenic

3.1

MutationTaster

Benign

1.0

A;A;A;A

PrimateAI

Benign

0.48

PROVEAN

Pathogenic

-5.0

REVEL

Pathogenic

0.83

Sift

Uncertain

0.0010

Sift4G

Uncertain

0.0050

Polyphen

0.069

Vest4

0.88

MutPred

0.97

Gain of methylation at I79 (P = 0.0208);

MVP

1.0

MPC

0.96

ClinPred

1.0

GERP RS

4.0

Varity_R

0.93

gMVP

0.88

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.21

Details are displayed if max score is > 0.2

DS_AG_spliceai

0.21

Position offset: -37

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over