20-18510875-C-T

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PP3PP5_Very_Strong

The NM_006363.6(SEC23B):c.40C>T(p.Arg14Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000124 in 1,613,968 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.00018 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

SEC23B
NM_006363.6 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:15

Conservation

PhyloP100: 2.06

Variant links:

Genes affected

SEC23B (HGNC:10702): (SEC23 homolog B, COPII coat complex component) The protein encoded by this gene is a member of the SEC23 subfamily of the SEC23/SEC24 family, which is involved in vesicle trafficking. The encoded protein has similarity to yeast Sec23p component of COPII. COPII is the coat protein complex responsible for vesicle budding from the ER. The function of this gene product has been implicated in cargo selection and concentration. Multiple alternatively spliced transcript variants have been identified in this gene. [provided by RefSeq, Feb 2010]

SEC23B links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.805

PP5

Variant 20-18510875-C-T is Pathogenic according to our data. Variant chr20-18510875-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1223.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SEC23B	NM_006363.6 link	c.40C>T	p.Arg14Trp	missense_variant	Exon 2 of 20	ENST00000650089.1	NP_006354.2	Q15437

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SEC23B	ENST00000650089.1 link	c.40C>T	p.Arg14Trp	missense_variant	Exon 2 of 20		NM_006363.6	ENSP00000497473.1		Q15437

Frequencies

GnomAD3 genomes

AF:

0.000178

AC:

AN:

152088

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000724

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000197

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000309

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000235

AC:

AN:

251450

Hom.:

AF XY:

0.000228

AC XY:

AN XY:

135900

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.000549

Gnomad ASJ exome

AF:

0.000198

Gnomad EAS exome

AF:

0.000163

Gnomad SAS exome

AF:

0.0000980

Gnomad FIN exome

AF:

0.0000462

Gnomad NFE exome

AF:

0.000237

Gnomad OTH exome

AF:

0.000489

GnomAD4 exome

AF:

0.000118

AC:

173

AN:

1461880

Hom.:

Cov.:

AF XY:

0.000124

AC XY:

AN XY:

727242

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000559

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000756

Gnomad4 SAS exome

AF:

0.0000580

Gnomad4 FIN exome

AF:

0.0000187

Gnomad4 NFE exome

AF:

0.000110

Gnomad4 OTH exome

AF:

0.000199

GnomAD4 genome

AF:

0.000178

AC:

AN:

152088

Hom.:

Cov.:

AF XY:

0.000148

AC XY:

AN XY:

74274

show subpopulations

Gnomad4 AFR

AF:

0.0000724

Gnomad4 AMR

AF:

0.000197

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000309

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000284

Hom.:

Bravo

AF:

0.000242

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.000233

AC:

ExAC

AF:

0.000165

AC:

EpiCase

AF:

0.000600

EpiControl

AF:

0.000296

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:15

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:8

Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Dec 01, 2024	SEC23B: PM3:Very Strong, PM2, PP3, PS3:Supporting -
Pathogenic, criteria provided, single submitter	clinical testing	Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital	Mar 04, 2025	- -
Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	May 30, 2023	- -
Pathogenic, no assertion criteria provided	clinical testing	Department of Pathology and Laboratory Medicine, Sinai Health System	-	The SEC23B p.R14W variant was identified in 36 of 178 proband chromosomes (frequency: 0.202; 1 homozygote, 3 heterozygotes, and 31 compound heterozygotes) from individuals or families with Congenital Dyserythropoietic Anemia type II (CDAII) (Punzo_2011_PMID:22208203; Russo_2011_PMID:21850656; Iolascon_2010_PMID:20015893; Bianchi_2009_PMID:19621418). A case report of an 18 year-old boy with chronic mild congenital anemia of unknown origin, chronic jaundice, and splenomegaly caused by non-autoimmune hemolytic anemia since 18 months of age was found to have two causative mutations in the SEC23B gene: the p.R14W variant and a novel frameshift deletion p.V164Wfs*3; the patientâ€šÃ„Ã´s non-consanguineous parents with no history of anemia were heterozygous for either mutation (Koker_2018_PMID:29846281). The variant was identified in dbSNP (ID: rs121918222) and ClinVar (classified as pathogenic by Invitae, GeneDx and EGL Genetic Diagnostics for congenital dyserythropoietic anemia, type II). The variant was identified in control databases in 67 of 282848 chromosomes at a frequency of 0.0002369 (Genome Aggregation Database March 6, 2019, v2.1.1). The variant was observed in the following populations: Latino in 21 of 35440 chromosomes (freq: 0.000593), Other in 4 of 7224 chromosomes (freq: 0.000554), European (non-Finnish) in 32 of 129154 chromosomes (freq: 0.000248), Ashkenazi Jewish in 2 of 10368 chromosomes (freq: 0.000193), East Asian in 3 of 19954 chromosomes (freq: 0.00015), South Asian in 3 of 30616 chromosomes (freq: 0.000098), African in 1 of 24972 chromosomes (freq: 0.00004), and European (Finnish) in 1 of 25120 chromosomes (freq: 0.00004). The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. The p.Arg14 residue is conserved in mammals but not in more distantly related organisms, and four out of five computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) suggest that the variant may impact the protein; however, this information is not predictive enough to assume pathogenicity. Functional studies demonstrated that the p.R14W variant resulted in <5% of detectable protein compared to wildtype, however the p.R14W variant was coimmunoprecipitated by SEC24D simlarly to wildtype (Schwarz_2009_PMID:19561605). In addition, Satchwell et al. conducted in vitro studies to track the appearance of the CDAII phenotype during erythroblast differentiation in 5 unrelated patients, 3 of whom were compound heterozygotes for the p.R14W variant; patient erythroblasts displayed the characteristic CDAII phenotype including multinuclearity, erythrocyte membrane protein hypoglycosylation, and residual endoplasmic reticulum (Satchwell_2013_PMID:23935019). In summary, based on the above information this variant meets our laboratoryâ€šÃ„Ã´s criteria to be classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	May 23, 2024	The SEC23B c.40C>T; p.Arg14Trp variant (rs121918222) has been reported in the literature as a founder mutation associated with congenital dyserythropoietic anemia type II in the Italian population (Russo 2011). In CDA II patients, the p.Arg14Trp variant was always detected along with an additional SEC23B pathogenic variant as a compound heterozygote (Aydin Koker 2018, Bianchi 2009, Iolascon 2010, Mansour-Hendili 2020, Mendez 2021, Moreno-Carralero 2018, Punzo 2011, Schwarz 2009). This SEC23B variant is reported as pathogenic in ClinVar (Variation ID: 1223). This variant is found in the general population with an overall allele frequency of 0.02% (67/282848 alleles) in the Genome Aggregation Database (v2.1.1). Computational analyses predict that this variant is deleterious (REVEL: 0.75). In addition, in vitro functional analyses demonstrate that Arg14Trp-mutated SEC23B is extremely unstable with less than 5% of residual protein activity (Schwarz 2009). Based on available information, this variant is considered to be pathogenic. References: Aydin Koker S et al. Identification of a Novel Mutation in the SEC23B Gene Associated With Congenital Dyserythropoietic Anemia Type II Through the Use of Next-generation Sequencing Panel in an Undiagnosed Case of Nonimmune Hereditary Hemolytic Anemia. J Pediatr Hematol Oncol. 2018 Oct. PMID: 29846281. Bianchi P et al. Congenital dyserythropoietic anemia type II (CDAII) is caused by mutations in the SEC23B gene. Hum Mutat. 2009 Sep. PMID: 19621418. Iolascon A et al. Molecular analysis of 42 patients with congenital dyserythropoietic anemia type II: new mutations in the SEC23B gene and a search for a genotype-phenotype relationship. Haematologica. 2010 May. PMID: 20015893. Mansour-Hendili L et al. Exome sequencing for diagnosis of congenital hemolytic anemia. Orphanet J Rare Dis. 2020 Jul 8. PMID: 32641076. Mendez M et al. Congenital dyserythropoietic anemia types Ib, II, and III: novel variants in the CDIN1 gene and functional study of a novel variant in the KIF23 gene. Ann Hematol. 2021 Feb. PMID: 33159567. Moreno-Carralero MI et al. Clinical and genetic features of congenital dyserythropoietic anemia (CDA). Eur J Haematol. 2018 Sep. PMID: 29901818. Punzo F et al. Congenital dyserythropoietic anemia type II: molecular analysis and expression of the SEC23B gene. Orphanet J Rare Dis. 2011 Dec 30. PMID: 2220820. Russo R et al. Two founder mutations in the SEC23B gene account for the relatively high frequency of CDA II in the Italian population. Am J Hematol. 2011 Sep. PMID: 21850656. Schwarz K et al. Mutations affecting the secretory COPII coat component SEC23B cause congenital dyserythropoietic anemia type II. Nature genetics. 2009 Aug. PMID: 19561605. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jun 20, 2022	One of the most common recurrent variants in the SEC23B gene and is considered a founder mutation in Italy, Morocco, and Israel (Russo et al., 2014); Published functional studies demonstrate a damaging effect: in vitro studies indicate the variant is unstable with less than 5% of the protein detectable compared to wild type (Schwarz et al., 2009); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 21850656, 23935019, 19621418, 29846281, 20015893, 22208203, 33159567, 19561605, 25044164, 34426522, 31589614, 32641076) -
Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Aug 26, 2015	- -
Pathogenic, criteria provided, single submitter	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Jul 23, 2024	- -

Congenital dyserythropoietic anemia, type II

Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Oxford Medical Genetics Laboratories, Oxford University Hospitals NHS Foundation Trust	Mar 23, 2023	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre	Mar 26, 2024	- -
Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	Oct 19, 2020	Based on the classification scheme VCGS_Germline_v1.3.3, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with congenital dyserythropoietic anemia type II (MIM#224100). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from arginine to tryptophan. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (67 heterozygotes, 0 homozygotes). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (v2) (1 heterozygote, 0 homozygotes) (I) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0604 - Variant is not located in an established domain, motif, hotspot or informative constraint region. (I) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This variant has been reported in a compound heterozygous state with another pathogenic variant in multiple individuals (ClinVar, PMID: 19621418, 19561605, 25044164). (SP) 1205 - This variant has been shown to be maternally inherited (VCGS #20G001494). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -
Pathogenic, no assertion criteria provided	literature only	OMIM	Sep 01, 2009	- -

Congenital dyserythropoietic anemia, type II;C4225179:Cowden syndrome 7

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Mar 10, 2024	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 27, 2025	This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 14 of the SEC23B protein (p.Arg14Trp). This variant is present in population databases (rs121918222, gnomAD 0.06%). This missense change has been observed in individual(s) with congenital dyserythropoietic anemia type II (PMID: 19561605, 19621418, 20015893, 21850656). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 1223). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt SEC23B protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects SEC23B function (PMID: 19561605). For these reasons, this variant has been classified as Pathogenic. -

SEC23B-related disorder

Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Mar 05, 2024

The SEC23B c.40C>T variant is predicted to result in the amino acid substitution p.Arg14Trp. This variant has been reported to be causative for autosomal recessive congenital dyserythropoietic anemia (CDA) type II in the homozygous or compound heterozygous states (Bianchi et al. 2009. PubMed ID: 19621418; Schwarz et al. 2009. PubMed ID: 19561605; Iolascon et al. 2010. PubMed ID: 20015893; Russo et al. 2011. PubMed ID: 21850656). This variant is reported in 0.059% of alleles in individuals of Latino descent in gnomAD. This variant is interpreted as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.59

BayesDel_addAF

Uncertain

0.080

BayesDel_noAF

Pathogenic

0.22

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Benign

0.17

T;T;.;T;T;.;.;.;T;T

Eigen

Uncertain

0.58

Eigen_PC

Uncertain

0.51

FATHMM_MKL

Uncertain

0.94

LIST_S2

Pathogenic

0.99

.;.;D;D;.;D;D;D;.;D

M_CAP

Uncertain

0.086

MetaRNN

Pathogenic

0.81

D;D;D;D;D;D;D;D;D;D

MetaSVM

Uncertain

0.63

MutationAssessor

Pathogenic

3.4

M;M;.;.;M;.;.;.;M;M

PrimateAI

Uncertain

0.75

PROVEAN

Pathogenic

-5.4

D;D;.;D;D;.;.;.;.;D

REVEL

Pathogenic

0.75

Sift

Benign

0.055

T;T;.;D;T;.;.;.;.;T

Sift4G

Uncertain

0.018

D;D;.;D;D;.;.;.;.;D

Polyphen

1.0

D;D;.;.;D;.;.;.;D;D

Vest4

0.72

MVP

0.93

MPC

0.60

ClinPred

0.80

GERP RS

4.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.31

gMVP

0.75

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over