rs3818903

Variant names:

• chr10-110600561-T-C
• rs3818903
• NM_005445.4:c.2535+15T>C

Your query was ambiguous. Multiple possible variants found:

• chr10-110600561-T-C
• chr10-110600561-T-G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_005445.4(SMC3):​c.2535+15T>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000844 in 1,184,174 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.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 8.4e-7 (0 hom.)
• Consequence: SMC3 NM_005445.4 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.818
• Publications: 0 publications found

Genes affected

SMC3 (HGNC:2468): (structural maintenance of chromosomes 3) This gene belongs to the SMC3 subfamily of SMC proteins. The encoded protein occurs in certain cell types as either an intracellular, nuclear protein or a secreted protein. The nuclear form, known as structural maintenance of chromosomes 3, is a component of the multimeric cohesin complex that holds together sister chromatids during mitosis, enabling proper chromosome segregation. Post-translational modification of the encoded protein by the addition of chondroitin sulfate chains gives rise to the secreted proteoglycan bamacan, an abundant basement membrane protein. [provided by RefSeq, Jul 2008]

SMC3 Gene-Disease associations (from GenCC):

• Cornelia de Lange syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• Cornelia de Lange syndrome 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.86).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SMC3	NM_005445.4	c.2535+15T>C		intron_variant	Intron 22 of 28	ENST00000361804.5	NP_005436.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SMC3	ENST00000361804.5	c.2535+15T>C		intron_variant	Intron 22 of 28	1	NM_005445.4	ENSP00000354720.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 8.44e-7 AC: 1 AN: 1184174 Hom.: 0 Cov.: 17 AF XY: 0.00 AC XY: 0 AN XY: 602460

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

African (AFR) AF: 0.00 AC: 0 AN: 27392

American (AMR) AF: 0.00 AC: 0 AN: 43434

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 24162

East Asian (EAS) AF: 0.00 AC: 0 AN: 37678

South Asian (SAS) AF: 0.00 AC: 0 AN: 79682

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52846

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5220

European-Non Finnish (NFE) AF: 0.00000116 AC: 1 AN: 862714

Other (OTH) AF: 0.00 AC: 0 AN: 51046

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.86
CADD	Benign	2.6
DANN	Benign	0.24
PhyloP100		0.82

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs3818903; hg19: chr10-112360319;