rs751279984
Variant summary
Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PM1PM5PP3_StrongPP5_Very_Strong
The NM_000352.6(ABCC8):c.1576C>T(p.Arg526Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000229 in 1,613,892 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R526L) has been classified as Likely pathogenic.
Frequency
Consequence
NM_000352.6 missense
Scores
Clinical Significance
Conservation
Publications
- hyperinsulinemic hypoglycemia, familial, 1Inheritance: AD, AR, SD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Illumina, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
- diabetes mellitus, permanent neonatal 3Inheritance: AR, SD, AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
- familial hyperinsulinismInheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health
- diabetes mellitusInheritance: SD Classification: DEFINITIVE Submitted by: Ambry Genetics
- monogenic diabetesInheritance: SD Classification: DEFINITIVE Submitted by: ClinGen
- diabetes mellitus, noninsulin-dependentInheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
- hypoglycemia, leucine-inducedInheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
- transient neonatal diabetes mellitusInheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Genomics England PanelApp
- permanent neonatal diabetes mellitusInheritance: AR, AD Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
- diabetes mellitus, transient neonatal, 2Inheritance: Unknown, AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
- pulmonary arterial hypertensionInheritance: AD Classification: MODERATE Submitted by: ClinGen
- autosomal dominant hyperinsulinism due to SUR1 deficiencyInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- DEND syndromeInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- diazoxide-resistant focal hyperinsulinism due to SUR1 deficiencyInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- maturity-onset diabetes of the youngInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- autosomal recessive hyperinsulinism due to SUR1 deficiencyInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- type 2 diabetes mellitusInheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
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ACMG classification
Our verdict: Pathogenic. The variant received 16 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000131 AC: 2AN: 152160Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.0000159 AC: 4AN: 251138 AF XY: 0.0000221 show subpopulations
GnomAD4 exome AF: 0.0000239 AC: 35AN: 1461732Hom.: 0 Cov.: 32 AF XY: 0.0000234 AC XY: 17AN XY: 727162 show subpopulations
GnomAD4 genome AF: 0.0000131 AC: 2AN: 152160Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74320 show subpopulations
ClinVar
Submissions by phenotype
Hyperinsulinemic hypoglycemia, familial, 1 Pathogenic:2
The p.Arg526Cys variant in ABCC8 has been previously reported in 5 individuals with hyperinsulinemic hypoglycemia (PMID: 23345197, 23652837, 25584046, 32170320, 27908292, 23275527), and has been seen in 0.004% (1/24950) of African/African American chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP: rs751279984). 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 (Variation ID: 553752) and has been interpreted as likely pathogenic by Counsyl and pathogenic by Invitae. Of the 5 affected individuals, 1 was a compound heterozygote that carried a likely pathogenic variant with unknown phase, and 3 were compound heterozygotes that carried a pathogenic/likely pathogenic variant in trans, which increases the likelihood that the p.Arg526Cys variant is pathogenic (Variation ID: 370909; PMID: 25584046, 32170320, 27908292, 23275527). In vitro functional studies provide some evidence that the p.Arg526Cys variant may slightly impact protein function (PMID: 25584046). However, these types of assays may not accurately represent biological function. Computational prediction tools and conservation analyses suggest that this variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In summary, although additional studies are required to fully establish its clinical significance, this variant is likely pathogenic for autosomal recessive hyperinsulinemic hypoglycemia. ACMG/AMP Criteria applied: PM3_strong, PP3, PM2_supporting, PS3_supporting (Richards 2015). -
This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -
Familial hyperinsulinism Pathogenic:1
Variant summary: ABCC8 c.1576C>T (p.Arg526Cys) results in a non-conservative amino acid change located in the ABC transporter type 1, transmembrane domain (IPR011527) of 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 1.6e-05 in 251138 control chromosomes. c.1576C>T has been reported in the literature as biallelic homozygous or compound heterozygous genotypes in multiple individuals affected with Congenital Hyperinsulinism (example, Arya_2014, Kapoor_2013, Salomon-Estebenez_2016, Mannisto_2020, Sogno-Valin_2013). These data indicate that the variant is very likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in reduced current flow under basal conditions as compared to wild-type and reduced responsiveness to diazoxide (Arya_2014). Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Type 2 diabetes mellitus Pathogenic:1
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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
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not provided Pathogenic:1
This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 526 of the ABCC8 protein (p.Arg526Cys). This variant is present in population databases (rs751279984, gnomAD 0.004%). This missense change has been observed in individual(s) with autosomal recessive congenital hyperinsulinism (PMID: 23275527, 23652837, 25584046, 27908292). 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: 553752). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt ABCC8 protein function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at