rs770371694

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 1P and 9B. PP2BP4_StrongBS1_SupportingBS2

The NM_015295.3(SMCHD1):​c.2731T>A​(p.Leu911Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000875 in 1,508,494 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000094 ( 1 hom. )

Consequence

SMCHD1
NM_015295.3 missense

Scores

1
5
13

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 2.35
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -8 ACMG points.

PP2
Missense variant in the SMCHD1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 23 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: 3.6318 (above the threshold of 3.09). Trascript score misZ: 3.965 (above the threshold of 3.09). GenCC associations: The gene is linked to facioscapulohumeral muscular dystrophy, arhinia, choanal atresia, and microphthalmia, hyposmia-nasal and ocular hypoplasia-hypogonadotropic hypogonadism syndrome.
BP4
Computational evidence support a benign effect (MetaRNN=0.0143763125).
BS1
Variant frequency is greater than expected in population eas. gnomad4 allele frequency = 0.0000329 (5/151992) while in subpopulation EAS AF= 0.000961 (5/5202). AF 95% confidence interval is 0.000379. There are 0 homozygotes in gnomad4. There are 4 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAd4 at 5 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SMCHD1NM_015295.3 linkc.2731T>A p.Leu911Ile missense_variant Exon 22 of 48 ENST00000320876.11 NP_056110.2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SMCHD1ENST00000320876.11 linkc.2731T>A p.Leu911Ile missense_variant Exon 22 of 48 5 NM_015295.3 ENSP00000326603.7 A6NHR9-1

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
151992
Hom.:
0
Cov.:
32
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:
0.000961
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
GnomAD3 exomes
AF:
0.0000458
AC:
7
AN:
152960
Hom.:
0
AF XY:
0.0000493
AC XY:
4
AN XY:
81136
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000667
Gnomad SAS 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:
0.0000936
AC:
127
AN:
1356502
Hom.:
1
Cov.:
24
AF XY:
0.0000911
AC XY:
61
AN XY:
669616
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00362
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.0000178
GnomAD4 genome
AF:
0.0000329
AC:
5
AN:
151992
Hom.:
0
Cov.:
32
AF XY:
0.0000539
AC XY:
4
AN XY:
74254
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000961
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000264
ExAC
AF:
0.0000993
AC:
11

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Facioscapulohumeral muscular dystrophy 2 Uncertain:1
Jun 22, 2023
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: 464165). This variant has not been reported in the literature in individuals affected with SMCHD1-related conditions. This variant is present in population databases (rs770371694, gnomAD 0.07%). This sequence change replaces leucine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 911 of the SMCHD1 protein (p.Leu911Ile). 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 not expected to disrupt SMCHD1 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. -

Inborn genetic diseases Uncertain:1
Mar 16, 2024
Ambry Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.2731T>A (p.L911I) alteration is located in exon 22 (coding exon 22) of the SMCHD1 gene. This alteration results from a T to A substitution at nucleotide position 2731, causing the leucine (L) at amino acid position 911 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.15
BayesDel_addAF
Benign
-0.33
T
BayesDel_noAF
Benign
-0.34
CADD
Benign
22
DANN
Benign
0.92
DEOGEN2
Benign
0.27
T
Eigen
Uncertain
0.40
Eigen_PC
Uncertain
0.35
FATHMM_MKL
Uncertain
0.89
D
LIST_S2
Benign
0.82
T
M_CAP
Benign
0.034
D
MetaRNN
Benign
0.014
T
MetaSVM
Benign
-0.81
T
MutationAssessor
Uncertain
2.3
M
PrimateAI
Uncertain
0.49
T
PROVEAN
Benign
-1.1
N
REVEL
Benign
0.13
Sift
Benign
0.17
T
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.46
MutPred
0.32
Loss of catalytic residue at L911 (P = 0.0331);
MVP
0.18
MPC
0.43
ClinPred
0.17
T
GERP RS
4.2
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.12
gMVP
0.36

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

LitVar

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

Other links and lift over

dbSNP: rs770371694; hg19: chr18-2726480; API