rs901512521

Positions:

• chr10-110602900-C-A
• chr10-110602900-C-G
• chr10-110602900-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP2 PP3

The NM_005445.4(SMC3):​c.3373C>A​(p.Leu1125Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L1125V) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SMC3 NM_005445.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.53

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 uncertain in NM_005445.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr10-110602900-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 436823.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SMC3. . Gene score misZ 6.3999 (greater than the threshold 3.09). Trascript score misZ 7.6232 (greater than threshold 3.09). GenCC has associacion of gene with Cornelia de Lange syndrome, Cornelia de Lange syndrome 3.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.76

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SMC3	NM_005445.4	c.3373C>A	p.Leu1125Ile	missense_variant	27/29	ENST00000361804.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SMC3	ENST00000361804.5	c.3373C>A	p.Leu1125Ile	missense_variant	27/29	1	NM_005445.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.83
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Uncertain	0.040
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Benign	0.23	T
Eigen	Uncertain	0.44
Eigen_PC	Uncertain	0.44
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.18	D
MetaRNN	Pathogenic	0.76	D
MetaSVM	Uncertain	0.36	D
MutationAssessor	Benign	1.7	L
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.87	D
PROVEAN	Benign	-1.9	N
REVEL	Uncertain	0.60
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.69
MutPred		0.68		Gain of methylation at K1120 (P = 0.0457);
MVP		0.83
MPC		2.2
ClinPred		0.96	D
GERP RS		5.6
Varity_R		0.70
gMVP		0.65

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

Publications

LitVar

Other links and lift over

dbSNP: rs901512521; hg19: chr10-112362658;