rs768951263

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_000352.6(ABCC8):​c.1254_1284dupTAATCTGGTTGCCATCGACACCAATCAGCTC​(p.Met429fs) variant causes a frameshift, stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000112 in 1,614,046 control chromosomes in the GnomAD database, with no homozygous occurrence. It is difficult to determine the true allele frequency of this variant because it is of type INS_BIG, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. L428L) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

ABCC8
NM_000352.6 frameshift, stop_gained

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:7

Conservation

PhyloP100: 0.726

Publications

1 publications found
Variant links:
Genes affected
ABCC8 (HGNC:59): (ATP binding cassette subfamily C member 8) The protein encoded by this gene is a member of the superfamily of ATP-binding cassette (ABC) transporters. ABC proteins transport various molecules across extra- and intra-cellular membranes. ABC genes are divided into seven distinct subfamilies (ABC1, MDR/TAP, MRP, ALD, OABP, GCN20, White). This protein is a member of the MRP subfamily which is involved in multi-drug resistance. This protein functions as a modulator of ATP-sensitive potassium channels and insulin release. Mutations in the ABCC8 gene and deficiencies in the encoded protein have been observed in patients with hyperinsulinemic hypoglycemia of infancy, an autosomal recessive disorder of unregulated and high insulin secretion. Mutations have also been associated with non-insulin-dependent diabetes mellitus type II, an autosomal dominant disease of defective insulin secretion. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jul 2020]
ABCC8 Gene-Disease associations (from GenCC):
  • hyperinsulinemic hypoglycemia, familial, 1
    Inheritance: AD, AR, SD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Illumina, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • diabetes mellitus, permanent neonatal 3
    Inheritance: AR, SD, AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
  • familial hyperinsulinism
    Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
  • diabetes mellitus
    Inheritance: SD Classification: DEFINITIVE Submitted by: Ambry Genetics
  • monogenic diabetes
    Inheritance: SD Classification: DEFINITIVE Submitted by: ClinGen
  • diabetes mellitus, noninsulin-dependent
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • hypoglycemia, leucine-induced
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
  • transient neonatal diabetes mellitus
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp
  • permanent neonatal diabetes mellitus
    Inheritance: AR, AD Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
  • diabetes mellitus, transient neonatal, 2
    Inheritance: Unknown, AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • pulmonary arterial hypertension
    Inheritance: AD Classification: MODERATE Submitted by: ClinGen
  • autosomal dominant hyperinsulinism due to SUR1 deficiency
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • DEND syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • diazoxide-resistant focal hyperinsulinism due to SUR1 deficiency
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • maturity-onset diabetes of the young
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • autosomal recessive hyperinsulinism due to SUR1 deficiency
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • type 2 diabetes mellitus
    Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 16 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PP5
Variant 11-17448563-T-TGAGCTGATTGGTGTCGATGGCAACCAGATTA is Pathogenic according to our data. Variant chr11-17448563-T-TGAGCTGATTGGTGTCGATGGCAACCAGATTA is described in ClinVar as Pathogenic. ClinVar VariationId is 434055.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
ABCC8NM_000352.6 linkc.1254_1284dupTAATCTGGTTGCCATCGACACCAATCAGCTC p.Met429fs frameshift_variant, stop_gained Exon 8 of 39 ENST00000389817.8 NP_000343.2 Q09428-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ABCC8ENST00000389817.8 linkc.1254_1284dupTAATCTGGTTGCCATCGACACCAATCAGCTC p.Met429fs frameshift_variant, stop_gained Exon 8 of 39 1 NM_000352.6 ENSP00000374467.4 Q09428-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152164
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
251476
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS 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:
0.0000116
AC:
17
AN:
1461882
Hom.:
0
Cov.:
31
AF XY:
0.0000138
AC XY:
10
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000153
AC:
17
AN:
1112002
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.490
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152164
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74316
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41438
American (AMR)
AF:
0.00
AC:
0
AN:
15270
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hyperinsulinemic hypoglycemia, familial, 1 Pathogenic:2
Mar 01, 2016
Genetic Services Laboratory, University of Chicago
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 16, 2023
Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:curation

The Met429Ter variant in ABCC8 has been reported in at least 5 individuals with congenital hyperinsulinism (PMID: 25201519, 23345197, 23275527), and has been identified in 0.004% (4/113754) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP rs768951263). Although this variant has been seen in the general population in a heterozygous state, its frequency is low enough to be consistent with a recessive carrier frequency. This variant has also been reported in ClinVar (VariationID: 434056) as pathogenic by Invitae, Genetic Services Laboratory (University of Chicago), Women's Health and Genetics/Laboratory Corporation of America (LabCorp), and Natera Inc. Of the 5 affected individuals, at least 1 was a compound heterozygote that carried a reported pathogenic variant in trans, which increases the likelihood that the Met429Ter variant is pathogenic (Variation ID: 370604; PMID: 23275527). This variant is predicted to cause a frameshift, which alters the protein’s amino acid sequence beginning at position 429 and leads to a premature termination codon 1 amino acid downstream. This alteration is then predicted to lead to a truncated or absent protein. Loss of function of the ABCC8 gene is an established disease mechanism in autosomal recessive hyperinsulinemic hypoglycemia. In summary, this variant meets criteria to be classified as pathogenic for autosomal recessive hyperinsulinemic hypoglycemia. ACMG/AMP Criteria applied: PVS1, PM3, PM2_supporting (Richards 2015). -

Familial hyperinsulinism Pathogenic:1
Oct 27, 2022
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: ABCC8 c.1254_1284dup31 (p.Met429X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 1.6e-05 in 251476 control chromosomes (gnomAD). c.1254_1284dup31 has been reported in the literature in multiple individuals affected with Congenital Hyperinsulinism (Banerjee_2011, Kapoor_2013, Snider_2013, Arya_2014, Demirbilek_2014). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Three ClinVar submitters have assessed the variant since 2014: all three classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Type 2 diabetes mellitus Pathogenic:1
Dec 05, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hereditary hyperinsulinism Pathogenic:1
Oct 14, 2021
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Type 2 diabetes mellitus;C0271714:Leucine-induced hypoglycemia;C1835887:Diabetes mellitus, transient neonatal, 2;C2931832:Hyperinsulinemic hypoglycemia, familial, 1;C5394303:Diabetes mellitus, permanent neonatal 3 Pathogenic:1
Apr 18, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Pathogenic:1
Jan 14, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Met429*) in the ABCC8 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in ABCC8 are known to be pathogenic (PMID: 20685672, 23345197). This variant is present in population databases (rs768951263, gnomAD 0.004%). This premature translational stop signal has been observed in individual(s) with autosomal recessive diffuse or paternally inherited focal hyperinsulinism (PMID: 25201519). ClinVar contains an entry for this variant (Variation ID: 434055). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
0.73
Mutation Taster
=3/197
disease causing (ClinVar)

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs768951263; hg19: chr11-17470110; API