2-232531600-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_000751.3(CHRND):​c.991C>T​(p.Leu331Phe) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,740 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. L331V) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

CHRND
NM_000751.3 missense

Scores

15
3
1

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 4.99

Publications

2 publications found
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 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.91

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNDNM_000751.3 linkc.991C>T p.Leu331Phe missense_variant Exon 9 of 12 ENST00000258385.8 NP_000742.1 Q07001-1
CHRNDNM_001256657.2 linkc.946C>T p.Leu316Phe missense_variant Exon 8 of 11 NP_001243586.1 Q07001-2
CHRNDNM_001311196.2 linkc.688C>T p.Leu230Phe missense_variant Exon 9 of 12 NP_001298125.1 Q07001
CHRNDNM_001311195.2 linkc.409C>T p.Leu137Phe missense_variant Exon 7 of 10 NP_001298124.1 Q07001B4E3W4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRNDENST00000258385.8 linkc.991C>T p.Leu331Phe missense_variant Exon 9 of 12 1 NM_000751.3 ENSP00000258385.3 Q07001-1

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251406
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461740
Hom.:
0
Cov.:
33
AF XY:
0.00000138
AC XY:
1
AN XY:
727176
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53278
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112006
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
31

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Lethal multiple pterygium syndrome Uncertain:1
Apr 20, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces leucine with phenylalanine at codon 331 of the CHRND protein (p.Leu331Phe). The leucine residue is highly conserved and there is a small physicochemical difference between leucine and phenylalanine. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a CHRND-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.72
BayesDel_addAF
Pathogenic
0.43
D
BayesDel_noAF
Pathogenic
0.48
CADD
Uncertain
25
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.88
.;D
Eigen
Pathogenic
0.96
Eigen_PC
Pathogenic
0.91
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.97
D;D
M_CAP
Uncertain
0.16
D
MetaRNN
Pathogenic
0.91
D;D
MetaSVM
Pathogenic
0.91
D
MutationAssessor
Pathogenic
4.5
.;H
PhyloP100
5.0
PrimateAI
Pathogenic
0.80
T
PROVEAN
Uncertain
-4.0
D;D
REVEL
Pathogenic
0.77
Sift
Pathogenic
0.0
D;D
Sift4G
Pathogenic
0.0
D;D
Polyphen
1.0
.;D
Vest4
0.84
MutPred
0.71
.;Loss of sheet (P = 0.302);
MVP
1.0
MPC
0.92
ClinPred
1.0
D
GERP RS
6.1
Varity_R
0.93
gMVP
0.75
Mutation Taster
=5/95
disease causing

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

Other links and lift over

dbSNP: rs1292476417; hg19: chr2-233396310; API