chr12-125767-C-T

Variant names:

• chr12-125767-C-T
• rs372928257
• NM_001170738.2:c.758C>T

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_Moderate BS2

The NM_001170738.2(IQSEC3):​c.758C>T​(p.Pro253Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000481 in 1,512,584 control chromosomes in the GnomAD database, including 2 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P253R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.00035 (0 hom., cov: 33)
  • Exomes 𝑓: 0.00050 (2 hom.)
• Consequence: IQSEC3 NM_001170738.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.12

Genes affected

IQSEC3 (HGNC:29193): (IQ motif and Sec7 domain ArfGEF 3) Predicted to enable guanyl-nucleotide exchange factor activity. Predicted to be involved in several processes, including actin cytoskeleton organization; activation of GTPase activity; and regulation of small GTPase mediated signal transduction. Located in cytosol and nucleoplasm. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.11215782).
• BS2: High Homozygotes in GnomAdExome4 at 2 gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
IQSEC3	NM_001170738.2	c.758C>T	p.Pro253Leu	missense_variant	Exon 3 of 14	ENST00000538872.6	NP_001164209.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
IQSEC3	ENST00000538872.6	c.758C>T	p.Pro253Leu	missense_variant	Exon 3 of 14	5	NM_001170738.2	ENSP00000437554.1
IQSEC3	ENST00000382841.2	c.-6-12500C>T		intron_variant	Intron 2 of 12	2		ENSP00000372292.2

Frequencies

GnomAD3 genomes AF: 0.000348 AC: 53 AN: 152178 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.000121

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000196

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000603

Gnomad OTH AF: 0.000956

GnomAD3 exomes AF: 0.000298 AC: 33 AN: 110634 Hom.: 0 AF XY: 0.000300 AC XY: 18 AN XY: 60088

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000237

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000104

Gnomad SAS exome AF: 0.000278

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.000513

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000495 AC: 674 AN: 1360406 Hom.: 2 Cov.: 30 AF XY: 0.000520 AC XY: 348 AN XY: 669712

Gnomad4 AFR exome AF: 0.000198

Gnomad4 AMR exome AF: 0.000278

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000170

Gnomad4 SAS exome AF: 0.000253

Gnomad4 FIN exome AF: 0.0000911

Gnomad4 NFE exome AF: 0.000563

Gnomad4 OTH exome AF: 0.000494

GnomAD4 genome AF: 0.000348 AC: 53 AN: 152178 Hom.: 0 Cov.: 33 AF XY: 0.000283 AC XY: 21 AN XY: 74328

Gnomad4 AFR AF: 0.000121

Gnomad4 AMR AF: 0.000196

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000193

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.000603

Gnomad4 OTH AF: 0.000956

Alfa AF: 0.000128 Hom.: 0

Bravo AF: 0.000438

TwinsUK AF: 0.00 AC: 0

ALSPAC AF: 0.000519 AC: 2

ESP6500AA AF: 0.000370 AC: 1

ESP6500EA AF: 0.000157 AC: 1

ExAC AF: 0.000147 AC: 15

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Jun 30, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.758C>T (p.P253L) alteration is located in exon 3 (coding exon 3) of the IQSEC3 gene. This alteration results from a C to T substitution at nucleotide position 758, causing the proline (P) at amino acid position 253 to be replaced by a leucine (L). 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	0.080
BayesDel_addAF	Benign	-0.58	T
BayesDel_noAF	Benign	-0.74
CADD	Benign	18
DANN	Uncertain	1.0
DEOGEN2	Benign	0.020	T
Eigen	Benign	-0.27
Eigen_PC	Benign	-0.20
FATHMM_MKL	Uncertain	0.81	D
LIST_S2	Benign	0.69	T
M_CAP	Uncertain	0.27	D
MetaRNN	Benign	0.11	T
MetaSVM	Benign	-0.98	T
MutationAssessor	Benign	0.55	N
PrimateAI	Uncertain	0.68	T
PROVEAN	Benign	-1.9	N
REVEL	Benign	0.079
Sift	Benign	0.10	T
Sift4G	Benign	0.21	T
Vest4		0.28
MVP		0.30
MPC		0.41
ClinPred		0.070	T
GERP RS		1.1
Varity_R		0.034
gMVP		0.20

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

Other links and lift over

dbSNP: rs372928257; hg19: chr12-234933;