rs117794949

Variant names:

• chr18-2750446-C-G
• rs117794949
• NM_015295.3:c.4104C>G

Your query was ambiguous. Multiple possible variants found:

• chr18-2750446-C-G
• chr18-2750446-C-T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP7

The NM_015295.3(SMCHD1):​c.4104C>G​(p.Pro1368Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,066 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. P1368P) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: SMCHD1 NM_015295.3 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.29
• Publications: 0 publications found

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

ENSG00000266049 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.46).
• BP7: Synonymous conserved (PhyloP=-1.29 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMCHD1	NM_015295.3	c.4104C>G	p.Pro1368Pro	synonymous_variant	Exon 32 of 48	ENST00000320876.11	NP_056110.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMCHD1	ENST00000320876.11	c.4104C>G	p.Pro1368Pro	synonymous_variant	Exon 32 of 48	5	NM_015295.3	ENSP00000326603.7

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459066 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 725666

African (AFR) AF: 0.00 AC: 0 AN: 33428

American (AMR) AF: 0.00 AC: 0 AN: 44326

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26000

East Asian (EAS) AF: 0.00 AC: 0 AN: 39588

South Asian (SAS) AF: 0.00 AC: 0 AN: 85930

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53304

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5750

European-Non Finnish (NFE) AF: 9.01e-7 AC: 1 AN: 1110462

Other (OTH) AF: 0.00 AC: 0 AN: 60278

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.46
CADD	Benign	1.1
DANN	Benign	0.66
PhyloP100		-1.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs117794949; hg19: chr18-2750444;