11-17427865-A-G

Variant names:

• chr11-17427865-A-G
• rs786204676
• NM_000352.6:c.2116+2T>C

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_000352.6(ABCC8):​c.2116+2T>C variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000684 in 1,461,712 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: ABCC8 NM_000352.6 splice_donor, intron
• Scores: Splicing: ADA: 0.9755
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:3 O:2
• Conservation: PhyloP100: 5.72

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]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-17427865-A-G is Pathogenic according to our data. Variant chr11-17427865-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 189078.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_risk_allele=2, Likely_pathogenic=3}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ABCC8	NM_000352.6	c.2116+2T>C		splice_donor_variant, intron_variant	Intron 15 of 38	ENST00000389817.8	NP_000343.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ABCC8	ENST00000389817.8	c.2116+2T>C		splice_donor_variant, intron_variant	Intron 15 of 38	1	NM_000352.6	ENSP00000374467.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000798 AC: 2 AN: 250658 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135458

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000177

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461712 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727116

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000899

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000508 Hom.: 0

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:3 Other:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hyperinsulinemic hypoglycemia, familial, 1 Pathogenic:2

Aug 16, 2023

Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

The c.2116+2T>C variant in ABCC8 has been reported in at least 1 individual with hyperinsulinemic hypoglycemia (PMID: 20685672, 22048969), and has been identified in 0.002% (2/113270) of European (non-Finnish) chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP ID: rs786204676). 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: 189078) and has been interpreted as likely pathogenic by Counsyl and Invitae, and as a variant of uncertain significance by Clinical Genomics (Uppaluri K&H Personalized Medicine Clinic). This variant is located in the 5' splice region. Computational tools predict a splicing impact, though this information is not predictive enough to determine pathogenicity. Loss of function of the ABCC8 gene is an established disease mechanism in autosomal recessive hyperinsulinemic hypoglycemia. 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: PVS1, PM2 (Richards 2015). -

Dec 04, 2014

Counsyl

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: literature only

- -

not provided Pathogenic:1

Jun 04, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is present in population databases (rs786204676, gnomAD 0.002%). This sequence change affects a donor splice site in intron 15 of the ABCC8 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in ABCC8 are known to be pathogenic (PMID: 20685672, 23345197). Disruption of this splice site has been observed in individual(s) with congenital hyperinsulinism (PMID: 20685672). 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. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 189078). -

Neonatal diabetes mellitus Other:1

May 27, 2024

Clinical Genomics, Uppaluri K&H Personalized Medicine Clinic

Significance: Uncertain risk allele

Review Status: flagged submission

Collection Method: research

This variant is found to be a potent moderate impact, deleterious variant with a CADD score of 29.3 and sufficient scientific evidence of gene-disease correlation. However, since this is not a high impact variant and no variant evidence, this variant is reclassified as Uncertain risk allele. -

Maturity onset diabetes mellitus in young Other:1

May 27, 2024

Clinical Genomics, Uppaluri K&H Personalized Medicine Clinic

Significance: Uncertain risk allele

Review Status: flagged submission

Collection Method: research

This variant is found to be a potent moderate impact, deleterious variant with a CADD score of 29.3 and sufficient scientific evidence of gene-disease correlation. However, since this is not a high impact variant and no variant evidence, this variant is reclassified as Uncertain risk allele. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.61	D
BayesDel_noAF	Uncertain	-0.070
CADD	Uncertain	25
DANN	Uncertain	0.98
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Uncertain	0.83	D
GERP RS		4.2

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.98
dbscSNV1_RF	Benign	0.55
SpliceAI score (max)		0.89		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.89		Position offset: 2

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

Publications

LitVar

Other links and lift over

dbSNP: rs786204676; hg19: chr11-17449412;