chr11-17387938-G-A

Position:

• chr11-17387938-G-A

Variant summary

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

The NM_000525.4(KCNJ11):​c.154C>T​(p.Gln52Ter) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000206 in 1,459,120 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 Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. Q52Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: KCNJ11 NM_000525.4 stop_gained
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:1
• Conservation: PhyloP100: 10.0

Genes affected

KCNJ11 (HGNC:6257): (potassium inwardly rectifying channel subfamily J member 11) Potassium channels are present in most mammalian cells, where they participate in a wide range of physiologic responses. The protein encoded by this gene is an integral membrane protein and inward-rectifier type potassium channel. The encoded protein, which has a greater tendency to allow potassium to flow into a cell rather than out of a cell, is controlled by G-proteins and is found associated with the sulfonylurea receptor SUR. Mutations in this gene are a cause of familial persistent hyperinsulinemic hypoglycemia of infancy (PHHI), an autosomal recessive disorder characterized by unregulated insulin secretion. Defects in this gene may also contribute to autosomal dominant non-insulin-dependent diabetes mellitus type II (NIDDM), transient neonatal diabetes mellitus type 3 (TNDM3), and permanent neonatal diabetes mellitus (PNDM). Multiple alternatively spliced transcript variants that encode different protein isoforms have been described for this gene. [provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 106 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-17387938-G-A is Pathogenic according to our data. Variant chr11-17387938-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 242910.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=1, Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNJ11	NM_000525.4	c.154C>T	p.Gln52Ter	stop_gained	1/1	ENST00000339994.5
KCNJ11	NM_001166290.2	c.-16-92C>T		intron_variant
KCNJ11	NM_001377296.1	c.-17+80C>T		intron_variant
KCNJ11	NM_001377297.1	c.-16-92C>T		intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNJ11	ENST00000339994.5	c.154C>T	p.Gln52Ter	stop_gained	1/1		NM_000525.4	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251206 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135780

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: 0.00000880

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000206 AC: 3 AN: 1459120 Hom.: 0 Cov.: 63 AF XY: 0.00000276 AC XY: 2 AN XY: 725212

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: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000468 Hom.: 0

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Type 2 diabetes mellitus Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Feb 08, 2024

- -

Hyperinsulinemic hypoglycemia, familial, 2 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Center of Genomic medicine, Geneva, University Hospital of Geneva

Mar 16, 2015

This recessive mutation in the KCNJ11 gene was found in a case of congenital hyperinsulinemic hypoglycemia. The combination of this mutation with a second recessive mutation (c.440T>C) in the same gene explains the phenotype of this newborn patient. -

Maturity onset diabetes mellitus in young Uncertain:1

Uncertain significance, criteria provided, single submitter

research

Clinical Genomics, Uppaluri K&H Personalized Medicine Clinic

-

Mutations in KCNJ11 gene can cause decreased production and secretion of insulin. This can lead to MODY which may be responsive to oral sulfonylureas. It is also associated with Neonatal Diabetes. However, no sufficient evidence is found to ascertain the role of rs879253757 variant in MODY yet. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	44
DANN	Uncertain	1.0
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Uncertain	0.95	D
MutationTaster	Benign	1.0	D;D
Vest4		0.82
GERP RS		4.6

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

Other links and lift over

dbSNP: rs879253757; hg19: chr11-17409485;