18-2656094-G-A

Variant summary

Our verdict is Benign. The variant received -8 ACMG points: 0P and 8B. BP4_StrongBS2

The NM_015295.3(SMCHD1):​c.19G>A​(p.Gly7Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000711 in 1,406,086 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000064 ( 0 hom. )

Consequence

SMCHD1
NM_015295.3 missense

Scores

2
17

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.0900

Publications

0 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: Benign. The variant received -8 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.06491363).
BS2
High AC in GnomAdExome4 at 8 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SMCHD1NM_015295.3 linkc.19G>A p.Gly7Ser 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.19G>A p.Gly7Ser missense_variant Exon 1 of 48 5 NM_015295.3 ENSP00000326603.7 A6NHR9-1
SMCHD1ENST00000688342.1 linkc.19G>A p.Gly7Ser missense_variant Exon 1 of 47 ENSP00000508422.1 A0A8I5KRS9
SMCHD1ENST00000684915.1 linkn.176G>A non_coding_transcript_exon_variant Exon 1 of 14
ENSG00000293256ENST00000733457.1 linkn.-224C>T upstream_gene_variant

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152172
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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
GnomAD2 exomes
AF:
0.0000223
AC:
2
AN:
89694
AF XY:
0.0000199
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000158
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000207
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000638
AC:
8
AN:
1253914
Hom.:
0
Cov.:
29
AF XY:
0.00000489
AC XY:
3
AN XY:
613194
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
25226
American (AMR)
AF:
0.00
AC:
0
AN:
15228
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
17984
East Asian (EAS)
AF:
0.00
AC:
0
AN:
29932
South Asian (SAS)
AF:
0.00
AC:
0
AN:
56372
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
44036
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4956
European-Non Finnish (NFE)
AF:
0.00000693
AC:
7
AN:
1009716
Other (OTH)
AF:
0.0000198
AC:
1
AN:
50464
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.444
Heterozygous variant carriers
0
1
2
2
3
4
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
AF:
0.0000131
AC:
2
AN:
152172
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74334
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41440
American (AMR)
AF:
0.0000654
AC:
1
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.600
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:
0.00000378
ExAC
AF:
0.00000849
AC:
1

ClinVar

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

Submissions by phenotype

Facioscapulohumeral muscular dystrophy 2 Uncertain:1
Nov 08, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 7 of the SMCHD1 protein (p.Gly7Ser). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with SMCHD1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1008120). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0". The serine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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
0.11
BayesDel_addAF
Benign
-0.25
T
BayesDel_noAF
Benign
-0.60
CADD
Benign
15
DANN
Benign
0.76
DEOGEN2
Benign
0.056
T
Eigen
Benign
-0.80
Eigen_PC
Benign
-0.75
FATHMM_MKL
Benign
0.043
N
LIST_S2
Benign
0.51
T
M_CAP
Uncertain
0.13
D
MetaRNN
Benign
0.065
T
MetaSVM
Benign
-0.99
T
MutationAssessor
Benign
-0.34
N
PhyloP100
0.090
PrimateAI
Uncertain
0.68
T
PROVEAN
Benign
-0.14
N
REVEL
Benign
0.027
Sift
Benign
0.21
T
Sift4G
Benign
0.42
T
Polyphen
0.0030
B
Vest4
0.089
MutPred
0.33
Gain of glycosylation at G7 (P = 2e-04);
MVP
0.093
MPC
0.65
ClinPred
0.030
T
GERP RS
2.3
PromoterAI
-0.0072
Neutral
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
2.3
Varity_R
0.042
gMVP
0.17
Mutation Taster
=89/11
polymorphism

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: rs762420641; hg19: chr18-2656093; API