11-17387224-C-T
Variant summary
Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM1PP5
The NM_000525.4(KCNJ11):c.868G>A(p.Val290Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000867 in 1,614,114 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_000525.4 missense
Scores
Clinical Significance
Conservation
Publications
- diabetes mellitus, transient neonatal, 3Inheritance: AD Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, G2P
- monogenic diabetesInheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
- hyperinsulinemic hypoglycemia, familial, 2Inheritance: AR, AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Myriad Women’s Health, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
- diabetes mellitus, noninsulin-dependentInheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
- diabetes mellitus, permanent neonatal 2Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
- maturity-onset diabetes of the young type 13Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
- autosomal dominant hyperinsulinism due to Kir6.2 deficiencyInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- DEND syndromeInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- intermediate DEND syndromeInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- maturity-onset diabetes of the youngInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- permanent neonatal diabetes mellitusInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- transient neonatal diabetes mellitusInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- autosomal recessive hyperinsulinism due to Kir6.2 deficiencyInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- diazoxide-resistant focal hyperinsulinism due to Kir6.2 deficiencyInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
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ACMG classification
Our verdict: Uncertain_significance. The variant received 3 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
KCNJ11 | NM_000525.4 | c.868G>A | p.Val290Met | missense_variant | Exon 1 of 1 | ENST00000339994.5 | NP_000516.3 | |
KCNJ11 | NM_001166290.2 | c.607G>A | p.Val203Met | missense_variant | Exon 2 of 2 | NP_001159762.1 | ||
KCNJ11 | NM_001377296.1 | c.607G>A | p.Val203Met | missense_variant | Exon 3 of 3 | NP_001364225.1 | ||
KCNJ11 | NM_001377297.1 | c.607G>A | p.Val203Met | missense_variant | Exon 2 of 2 | NP_001364226.1 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152222Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.0000199 AC: 5AN: 251416 AF XY: 0.0000294 show subpopulations
GnomAD4 exome AF: 0.00000889 AC: 13AN: 1461892Hom.: 0 Cov.: 68 AF XY: 0.0000110 AC XY: 8AN XY: 727246 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152222Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1AN XY: 74366 show subpopulations ⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
Age Distribution
ClinVar
Submissions by phenotype
Familial hyperinsulinism Pathogenic:1
Variant summary: KCNJ11 c.868G>A (p.Val290Met) results in a conservative amino acid change located in the Inward rectifier potassium channel, C-terminal (IPR041647) of the encoded protein sequence. Three 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 251416 control chromosomes. c.868G>A has been reported in the literature either at a homozygous state or at a heterozygous state in at-least two unrelated individuals affected with Familial Hyperinsulinism (example, Loechner_2011, Maiorana_2014). In the family with a proband carrying the homozygous variant, two of clinically unaffected carriers with the heterozygous variant reported abnormally enhanced glucose tolerance. This variant, at a heterozygous state was also identified in patients with type 1 diabetes and unspecified carrier(s) without Diabetes (Sanyoura_2018, Billings_2022). These data indicate that the variant may be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in diminished Potassium channel activity when expressed homomerically, and to a lesser extent (about 50%) when expressed heteromerically with wild-type subunit in COSm6 cells (Loechner_2011), suggesting of a loss-of-function variant. The following publications have been ascertained in the context of this evaluation (PMID: 36208030, 20980454, 24383515, 28938416). ClinVar contains an entry for this variant (Variation ID: 435556). Based on the evidence outlined above, the variant was classified as likely pathogenic. -
Type 2 diabetes mellitus Pathogenic:1
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Type 2 diabetes mellitus;C1864623:Diabetes mellitus, transient neonatal, 3;C2931833:Hyperinsulinemic hypoglycemia, familial, 2;C4225365:Maturity-onset diabetes of the young type 13;C5394296:Diabetes mellitus, permanent neonatal 2 Pathogenic:1
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Hyperinsulinemic hypoglycemia, familial, 2 Pathogenic:1
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Hyperinsulinemia Uncertain:1
Mutations in KCNJ 11 gene can cause decreased production and secretion of insulin. This can lead to MODY which may be responsive to oral sulfonylureas. However, this particular variant (rs750414160) of KCNJ11 gene can inactivate KATP channels that can inturn lead to hyperinsulinemia. More studies are required to ascertain the role of this particular variant (rs750414160) in MODY. -
not provided Uncertain:1
This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 290 of the KCNJ11 protein (p.Val290Met). This variant is present in population databases (rs750414160, gnomAD 0.01%). This missense change has been observed in individuals with autosomal recessive diffuse or focal hyperinsulinism and/or diabetes mellitus (PMID: 20980454, 28938416). ClinVar contains an entry for this variant (Variation ID: 435556). 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) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on KCNJ11 protein function. Experimental studies have shown that this missense change affects KCNJ11 function (PMID: 20980454). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at