rs797045994

Variant names:

• chrX-53382363-G-A
• rs797045994
• NM_006306.4:c.3306C>T

Your query was ambiguous. Multiple possible variants found:

• chrX-53382363-G-A
• chrX-53382363-G-C

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_006306.4(SMC1A):​c.3306C>T​(p.Asn1102Asn) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,095,221 control chromosomes in the GnomAD database, with no homozygous occurrence. There are no hemizygote samples in GnomAD. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: not found (cov: 22)
  • Exomes 𝑓: 0.0000027 (0 hom. 0 hem.)
• Consequence: SMC1A NM_006306.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 1.65
• Publications: 0 publications found

Genes affected

SMC1A (HGNC:11111): (structural maintenance of chromosomes 1A) Proper cohesion of sister chromatids is a prerequisite for the correct segregation of chromosomes during cell division. The cohesin multiprotein complex is required for sister chromatid cohesion. This complex is composed partly of two structural maintenance of chromosomes (SMC) proteins, SMC3 and either SMC1B or the protein encoded by this gene. Most of the cohesin complexes dissociate from the chromosomes before mitosis, although those complexes at the kinetochore remain. Therefore, the encoded protein is thought to be an important part of functional kinetochores. In addition, this protein interacts with BRCA1 and is phosphorylated by ATM, indicating a potential role for this protein in DNA repair. This gene, which belongs to the SMC gene family, is located in an area of the X-chromosome that escapes X inactivation. Mutations in this gene result in Cornelia de Lange syndrome. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jul 2013]

SMC1A Gene-Disease associations (from GenCC):

• Cornelia de Lange syndrome 2

  Inheritance: XL Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• developmental and epileptic encephalopathy, 85, with or without midline brain defects

  Inheritance: XL Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• X-linked complex neurodevelopmental disorder

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
• atypical Rett syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Cornelia de Lange syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.59).
• BP6: Variant X-53382363-G-A is Benign according to our data. Variant chrX-53382363-G-A is described in ClinVar as Likely_benign. ClinVar VariationId is 1553627.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=1.65 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMC1A	NM_006306.4	c.3306C>T	p.Asn1102Asn	synonymous_variant	Exon 22 of 25	ENST00000322213.9	NP_006297.2
SMC1A	NM_001281463.1	c.3240C>T	p.Asn1080Asn	synonymous_variant	Exon 23 of 26		NP_001268392.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMC1A	ENST00000322213.9	c.3306C>T	p.Asn1102Asn	synonymous_variant	Exon 22 of 25	1	NM_006306.4	ENSP00000323421.3

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome AF: 0.00000274 AC: 3 AN: 1095221 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 360781

African (AFR) AF: 0.00 AC: 0 AN: 26355

American (AMR) AF: 0.00 AC: 0 AN: 34849

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 19326

East Asian (EAS) AF: 0.00 AC: 0 AN: 30123

South Asian (SAS) AF: 0.00 AC: 0 AN: 53630

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 40379

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4133

European-Non Finnish (NFE) AF: 0.00000357 AC: 3 AN: 840440

Other (OTH) AF: 0.00 AC: 0 AN: 45986

GnomAD4 genome Cov.: 22

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital muscular hypertrophy-cerebral syndrome Benign:1

Oct 03, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.59
CADD	Benign	4.9
DANN	Benign	0.69
PhyloP100		1.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.7

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

Other links and lift over

dbSNP: rs797045994; hg19: chrX-53409284;