18-2656090-C-G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_015295.3(SMCHD1):​c.15C>G​(p.Asp5Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,104 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Synonymous variant affecting the same amino acid position (i.e. D5D) has been classified as Likely benign.

Frequency

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

Consequence

SMCHD1
NM_015295.3 missense

Scores

1
18

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.172

Publications

1 publications found
Variant links:
Genes affected
SMCHD1 (HGNC:29090): (structural maintenance of chromosomes flexible hinge domain containing 1) This gene encodes a protein which contains a hinge region domain found in members of the SMC (structural maintenance of chromosomes) protein family. [provided by RefSeq, Dec 2011]
SMCHD1 Gene-Disease associations (from GenCC):
  • arhinia, choanal atresia, and microphthalmia
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, G2P, Ambry Genetics, ClinGen, Illumina
  • facioscapulohumeral muscular dystrophy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • hyposmia-nasal and ocular hypoplasia-hypogonadotropic hypogonadism syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.043758363).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SMCHD1NM_015295.3 linkc.15C>G p.Asp5Glu missense_variant Exon 1 of 48 ENST00000320876.11 NP_056110.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SMCHD1ENST00000320876.11 linkc.15C>G p.Asp5Glu missense_variant Exon 1 of 48 5 NM_015295.3 ENSP00000326603.7 A6NHR9-1
SMCHD1ENST00000688342.1 linkc.15C>G p.Asp5Glu missense_variant Exon 1 of 47 ENSP00000508422.1 A0A8I5KRS9
SMCHD1ENST00000684915.1 linkn.172C>G non_coding_transcript_exon_variant Exon 1 of 14
ENSG00000293256ENST00000733457.1 linkn.-220G>C upstream_gene_variant

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152104
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
Cov.:
29
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152104
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74304
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41426
American (AMR)
AF:
0.00
AC:
0
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5178
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67990
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151

ClinVar

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

Submissions by phenotype

Facioscapulohumeral muscular dystrophy 2 Uncertain:1
Jul 12, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with glutamic acid, which is acidic and polar, at codon 5 of the SMCHD1 protein (p.Asp5Glu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SMCHD1-related conditions. Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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
Benign
0.086
BayesDel_addAF
Benign
-0.36
T
BayesDel_noAF
Benign
-0.75
CADD
Benign
13
DANN
Benign
0.89
DEOGEN2
Benign
0.053
T
Eigen
Benign
-0.80
Eigen_PC
Benign
-0.73
FATHMM_MKL
Benign
0.090
N
LIST_S2
Benign
0.40
T
M_CAP
Benign
0.044
D
MetaRNN
Benign
0.044
T
MetaSVM
Benign
-0.99
T
MutationAssessor
Benign
0.0
N
PhyloP100
-0.17
PrimateAI
Uncertain
0.70
T
PROVEAN
Benign
-0.21
N
REVEL
Benign
0.024
Sift
Benign
0.65
T
Sift4G
Benign
0.98
T
Polyphen
0.048
B
Vest4
0.027
MutPred
0.25
Gain of sheet (P = 0.1945);
MVP
0.11
MPC
0.61
ClinPred
0.051
T
GERP RS
1.8
PromoterAI
-0.088
Neutral
Varity_R
0.088
gMVP
0.099

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: rs769401596; hg19: chr18-2656089; API