20-18510888-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PP3_ModeratePP5

The NM_006363.6(SEC23B):​c.53G>A​(p.Arg18His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000186 in 1,614,054 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely benign in UniProt.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

SEC23B
NM_006363.6 missense

Scores

14
3
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:5U:1

Conservation

PhyloP100: 10.0
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 3 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.897
PP5
Variant 20-18510888-G-A is Pathogenic according to our data. Variant chr20-18510888-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 1701418.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=4, Uncertain_significance=1, Pathogenic=1}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SEC23BNM_006363.6 linkc.53G>A p.Arg18His 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
SEC23BENST00000650089.1 linkc.53G>A p.Arg18His missense_variant Exon 2 of 20 NM_006363.6 ENSP00000497473.1 Q15437

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152170
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000262
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000199
AC:
5
AN:
251472
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135910
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000352
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000157
AC:
23
AN:
1461884
Hom.:
0
Cov.:
32
AF XY:
0.0000138
AC XY:
10
AN XY:
727246
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000171
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000460
AC:
7
AN:
152170
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74348
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.000262
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000564
Hom.:
0
Bravo
AF:
0.0000227
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.000109
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:5Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Congenital dyserythropoietic anemia, type II;C4225179:Cowden syndrome 7 Pathogenic:2
Apr 04, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Nov 11, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 18 of the SEC23B protein (p.Arg18His). This variant is present in population databases (no rsID available, gnomAD 0.003%). This missense change has been observed in individuals with dyserythropoietic anemia type 2 (PMID: 19561605, 27471141). ClinVar contains an entry for this variant (Variation ID: 1701418). 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%. This variant disrupts the p.Arg18 amino acid residue in SEC23B. Other variant(s) that disrupt this residue have been observed in individuals with SEC23B-related conditions (PMID: 27471141), which suggests that this may be a clinically significant amino acid residue. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

not provided Pathogenic:2
Aug 26, 2024
GeneDx
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Observed in patients with features of congenital dyserythropoietic anemia type II who also possessed a second SEC23B variant (PMID: 19561605, 27471141, 20015893); Not observed at significant frequency in large population cohorts (gnomAD); 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: 19561605, 20015893, 27471141, 31104444, Melanie2012[poster]) -

Dec 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

SEC23B: PM2, PM5, PP3, PP4 -

Congenital dyserythropoietic anemia, type II Pathogenic:1
Oct 08, 2024
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, 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 anaemia type II (CDA; 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 histidine. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD <0.01 for a recessive condition (v3: 7 heterozygotes, 0 homozygotes). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (highest allele count v3: 3 heterozygotes, 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) 0704 - Another missense variant comparable to the one identified in this case has limited previous evidence for pathogenicity. p.(Arg18Cys) has been reported in an individual with CDA and compound heterozygous with p.(Arg14Trp) (PMID: 27471141). (SP) 0802 - This variant has moderate previous evidence of pathogenicity in unrelated individuals. It has been reported in at least four compound heterozygous individuals with CDA (PMID: 20015893, 25044164, 27471141). In addition, it has been classified as a variant of uncertain significance and likely pathogenic by diagnostic laboratories in ClinVar. (SP) 1007 - No published functional evidence has been identified for this variant. (I) 1101 - Very strong and specific phenotype match for this individual. (SP) 1201 - Heterozygous variant detected in trans with a second pathogenic heterozygous variant (NM_006363.6(SEC23B):c.279+2T>C) in a recessive disease. (SP) 1205 - This variant has been shown to be maternally inherited (by trio analysis). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

not specified Uncertain:1
Mar 22, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: SEC23B c.53G>A (p.Arg18His) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2e-05 in 251472 control chromosomes. c.53G>A has been reported in the literature in at-least two individuals affected with Congenital dyserythropoietic anemia, type II (Iolascon_2010, Schwarz_ 2009). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 20015893, 19561605). ClinVar contains an entry for this variant (Variation ID: 1701418). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.89
BayesDel_addAF
Pathogenic
0.43
D
BayesDel_noAF
Pathogenic
0.46
CADD
Pathogenic
34
DANN
Pathogenic
1.0
DEOGEN2
Benign
0.41
T;T;.;T;T;.;.;.;T;T
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.93
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.95
.;.;D;D;.;D;D;D;.;D
M_CAP
Uncertain
0.19
D
MetaRNN
Pathogenic
0.90
D;D;D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
0.94
D
MutationAssessor
Pathogenic
4.2
H;H;.;.;H;.;.;.;H;H
PrimateAI
Pathogenic
0.86
D
PROVEAN
Uncertain
-4.3
D;D;.;D;D;.;.;.;.;D
REVEL
Pathogenic
0.87
Sift
Pathogenic
0.0
D;D;.;D;D;.;.;.;.;D
Sift4G
Pathogenic
0.0010
D;D;.;D;D;.;.;.;.;D
Polyphen
1.0
D;D;.;.;D;.;.;.;D;D
Vest4
0.98
MVP
0.98
MPC
0.77
ClinPred
1.0
D
GERP RS
5.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.71
gMVP
0.87

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.

Other links and lift over

dbSNP: rs905074313; hg19: chr20-18491532; API