18-2732461-A-G

Variant names:

Variant summary

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

The NM_015295.3(SMCHD1):c.3245A>G(p.Asn1082Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000809 in 1,607,866 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

SMCHD1
NM_015295.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 1.25

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

SMCHD1 links:

ENSG00000266049 (HGNC:):

ENSG00000266049 links:

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=0.03046748).

BS2

High AC in GnomAdExome4 at 12 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMCHD1	NM_015295.3 link	c.3245A>G	p.Asn1082Ser	missense_variant	Exon 25 of 48	ENST00000320876.11	NP_056110.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMCHD1	ENST00000320876.11 link	c.3245A>G	p.Asn1082Ser	missense_variant	Exon 25 of 48	5	NM_015295.3	ENSP00000326603.7		A6NHR9-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152226

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:

0.000193

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

GnomAD2 exomes

AF:

0.00000818

AC:

AN:

244378

AF XY:

0.0000151

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000294

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:

0.00000824

AC:

AN:

1455640

Hom.:

Cov.:

AF XY:

0.00000690

AC XY:

AN XY:

724180

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33350

American (AMR)

AF:

0.000113

AC:

AN:

44396

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26046

East Asian (EAS)

AF:

0.000101

AC:

AN:

39584

South Asian (SAS)

AF:

0.0000116

AC:

AN:

85988

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53318

Middle Eastern (MID)

AF:

0.00

AC:

AN:

4490

European-Non Finnish (NFE)

AF:

0.00000180

AC:

AN:

1108388

Other (OTH)

AF:

0.00

AC:

AN:

60080

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.513

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152226

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74376

show subpopulations

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.00

AC:

AN:

41466

American (AMR)

AF:

0.00

AC:

AN:

15284

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.000193

AC:

AN:

5192

South Asian (SAS)

AF:

0.00

AC:

AN:

4838

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10630

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68026

Other (OTH)

AF:

0.00

AC:

AN:

2092

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.375

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.00000378

ExAC

AF:

0.00000828

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Facioscapulohumeral muscular dystrophy 2

Uncertain:1

Aug 07, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

ClinVar contains an entry for this variant (Variation ID: 283238). 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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated. This variant has not been reported in the literature in individuals affected with SMCHD1-related conditions. This variant is present in population databases (rs756368420, gnomAD 0.003%). This sequence change replaces asparagine, which is neutral and polar, with serine, which is neutral and polar, at codon 1082 of the SMCHD1 protein (p.Asn1082Ser). -

Inborn genetic diseases

Uncertain:1

Apr 18, 2025

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The c.3245A>G (p.N1082S) alteration is located in exon 25 (coding exon 25) of the SMCHD1 gene. This alteration results from a A to G substitution at nucleotide position 3245, causing the asparagine (N) at amino acid position 1082 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Sep 10, 2015

Eurofins Ntd Llc (ga)

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.064

BayesDel_addAF

Benign

-0.42

BayesDel_noAF

Benign

-0.74

CADD

Benign

(source)

DANN

Benign

0.78

DEOGEN2

Benign

0.057

Eigen

Benign

-0.70

Eigen_PC

Benign

-0.49

FATHMM_MKL

Benign

0.13

LIST_S2

Benign

0.76

M_CAP

Benign

0.0055

MetaRNN

Benign

0.030

MetaSVM

Benign

-0.97

MutationAssessor

Benign

0.34

PhyloP100

1.2

PrimateAI

Benign

0.28

PROVEAN

Benign

0.17

REVEL

Benign

0.088

Sift

Benign

1.0

Sift4G

Benign

0.75

Polyphen

0.0

Vest4

0.12

MutPred

0.28

Gain of glycosylation at N1082 (P = 0.036);

MVP

0.082

MPC

0.17

ClinPred

0.032

GERP RS

4.1

Varity_R

0.028

gMVP

0.091

Mutation Taster

=94/6

polymorphism

(source)

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

18-2732461-A-G

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over