rs202039659
Variant summary
Our verdict is Benign. Variant got -8 ACMG points: 1P and 9B. BA1BP5PP3
This summary comes from the ClinGen Evidence Repository: The c.1541A>G variant in the HNF1 homeobox A gene, HNF1A, causes an amino acid change of histidine to arginine at codon 514 (p.(His514Arg)) of NM_000545.8. This variant is predicted to be deleterious by computational evidence, with a REVEL score of 0.85, which is greater than the MDEP VCEP threshold of 0.70 (PP3). However, this variant has a Grpmax Filtering allele frequency in gnomAD 2.1.1 of 0.0001150, which is greater than the MDEP threshold for BA1 (0.0001) (BA1). Additionally, this variant was identified in a patient with an alternate molecular basis for disease (BP5; internal lab contributors). In summary, c.1541A>G meets the criteria to be classified as benign for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP (specification version 2.1.0, approved 08/11/2023): BA1, BP5, PP3. While this variant is benign for HNF1A-monogenic diabetes, there is evidence to suggest that this variant may act as a risk allele for type 2 diabetes (PMID:11692182, 27899486, 36216889, 33046911). LINK:https://erepo.genome.network/evrepo/ui/classification/CA6832103/MONDO:0015967/017
Frequency
Consequence
NM_000545.8 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Benign. Variant got -8 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
HNF1A | NM_000545.8 | c.1541A>G | p.His514Arg | missense_variant | Exon 8 of 10 | ENST00000257555.11 | NP_000536.6 | |
HNF1A | NM_001306179.2 | c.1541A>G | p.His514Arg | missense_variant | Exon 8 of 10 | NP_001293108.2 | ||
HNF1A | NM_001406915.1 | c.1349A>G | p.His450Arg | missense_variant | Exon 7 of 9 | NP_001393844.1 | ||
HNF1A | XM_024449168.2 | c.1541A>G | p.His514Arg | missense_variant | Exon 8 of 9 | XP_024304936.1 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
HNF1A | ENST00000257555.11 | c.1541A>G | p.His514Arg | missense_variant | Exon 8 of 10 | 1 | NM_000545.8 | ENSP00000257555.5 |
Frequencies
GnomAD3 genomes AF: 0.000270 AC: 41AN: 151994Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.000430 AC: 108AN: 251200Hom.: 0 AF XY: 0.000420 AC XY: 57AN XY: 135872
GnomAD4 exome AF: 0.000233 AC: 340AN: 1461718Hom.: 1 Cov.: 32 AF XY: 0.000226 AC XY: 164AN XY: 727166
GnomAD4 genome AF: 0.000270 AC: 41AN: 152110Hom.: 0 Cov.: 32 AF XY: 0.000256 AC XY: 19AN XY: 74352
ClinVar
Submissions by phenotype
not specified Uncertain:2Benign:1
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Variant summary: HNF1A c.1541A>G (p.His514Arg) results in a non-conservative amino acid change located in the Hepatocyte nuclear factor 1, beta isoform, C-terminal domain (IPR006897) 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 0.00024 in 1613828 control chromosomes in the gnomAD database, including 1 homozygotes. The observed variant frequency is approximately 9 fold of the estimated maximal expected allele frequency for a pathogenic variant in HNF1A causing Maturity Onset Diabetes Of The Young 3 phenotype (2.5e-05), strongly suggesting that the variant is benign. c.1541A>G has been reported in the literature in individuals affected with diabetes and individuals from MODY cohort studies without strong evidence of segregation (examples: Behn_1998, Gragnoli_2001,Flannick_2013, Karaca_2017, Yu_2019, Elashi_2022). These report(s) do not provide unequivocal conclusions about association of the variant with Maturity Onset Diabetes Of The Young 3. At least one publication reports experimental evidence that this variant had a reduction in transcriptional activity and abnormal nuclear localization compared to Wild-Type (Najmi_2017). The following publications have been ascertained in the context of this evaluation (PMID: 9604876, 36613572, 24097065, 11692182, 28395978, 27899486, 10333057, 31264968). Nine submitters have cited clinical-significance assessments for this variant to ClinVar after 2014 and classified this variant as VUS (n=8) and Benign (n=1). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -
The p.His514Arg variant in HNF1A is classified as likely benign because it has been identified in 0.8% (83/10366) of Ashkenazi Jewish chromosomes by gnomAD (http://gnomad.broadinstitute.org). Computational prediction tools and conservation analyses do not provide strong support for or against an impact to the protein. ACMG/AMP Criteria applied: BS1. -
not provided Uncertain:2Benign:1
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In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 32910913, 31264968, 28395978, 27899486, 24097065, 11692182) -
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Maturity-onset diabetes of the young type 3 Uncertain:2
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This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -
Monogenic diabetes Uncertain:1Benign:1
ACMG Criteria:PP3 (8 predictors), BP4 (2 predictors), PS3 (PMID: 27899486 shows decreased activity and altered localization) -
The c.1541A>G variant in the HNF1 homeobox A gene, HNF1A, causes an amino acid change of histidine to arginine at codon 514 (p.(His514Arg)) of NM_000545.8. This variant is predicted to be deleterious by computational evidence, with a REVEL score of 0.85, which is greater than the MDEP VCEP threshold of 0.70 (PP3). However, this variant has a Grpmax Filtering allele frequency in gnomAD 2.1.1 of 0.0001150, which is greater than the MDEP threshold for BA1 (0.0001) (BA1). Additionally, this variant was identified in a patient with an alternate molecular basis for disease (BP5; internal lab contributors). In summary, c.1541A>G meets the criteria to be classified as benign for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP (specification version 2.1.0, approved 08/11/2023): BA1, BP5, PP3. While this variant is benign for HNF1A-monogenic diabetes, there is evidence to suggest that this variant may act as a risk allele for type 2 diabetes (PMID: 11692182, 27899486, 36216889, 33046911). -
Maturity onset diabetes mellitus in young Uncertain:1
The p.H514R variant (also known as c.1541A>G), located in coding exon 8 of the HNF1A gene, results from an A to G substitution at nucleotide position 1541. The histidine at codon 514 is replaced by arginine, an amino acid with highly similar properties. This variant was first reported in a 29-year-old female and her mother, who were both diagnosed with type 2 diabetes (Gragnoli C et al. Diabetologia, 2001 Oct;44:1326-9). In another study, this variant was identified in a sample submitted for maturity-onset diabetes of the young genetic testing; however, specific clinical information was not provided and this variant was reported as a variant of uncertain significance (Bennett JT et al. Mol. Genet. Metab., 2015 Mar;114:451-8). This variant was also identified in a cohort of individuals with diabetes as well as in an 18-year-old female with negative autoantibodies and no family history of diabetes (Flannick J et al. Nat. Genet., 2013 Nov;45:1380-5; Karaca E et al. Diabetes Metab Syndr, 2017 Nov;11 Suppl 1:S491-S496). Functional analyses in HeLa cells demonstrated a reduction of transcriptional activity and nuclear localization compared to wild type, but at higher levels than known mutations in the HNF1A gene (Najmi LA et al. Diabetes, 2017 02;66:335-346). Based on data from gnomAD, the G allele has an overall frequency of approximately 0.039% (109/276936) total alleles studied. The highest observed frequency was 0.807% (82/10150) of Ashkenazi Jewish alleles. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on available evidence to date, the clinical significance of this alteration remains unclear. -
Diabetes mellitus type 1;C0011860:Type 2 diabetes mellitus;C1838100:Maturity-onset diabetes of the young type 3;C2675866:Type 1 diabetes mellitus 20 Uncertain:1
The c.1541A>G variant identified in the HNF1A gene has been previously reported in individuals with diabetes in the literature [PMID:31264968, 28395978, 27899486, others], however it has also been reported in individuals without family history of diabetes [PMID: 31264968]. This variant has been reported in ClinVar as both a Variant of Uncertain Significance and as Likely Benign (VarID:435421). The c.1541A>G variant is observed in population databases (gnomADv2.1, gnomADv3.1.2, BRAVO-TOPMed) with highest allele frequency of 3.96e-4-4 (112 heterozygotes, 0 homozygotes, gnomADv2.1). The c.1541A>G variant is located within exon 8 of this 10-exon gene and is predicted to substitute a evolutionarily well conserved Histidine for Arginine at amino acid 514/632 (p.(His514Arg)),outside of predicted domains of HNF1A (UniProtKB:P20823). In silico algorithms predict this variant to have a damaging effect to protein function (REVEL=0.85) and this is supported by in vitro functional studies suggest that the p.His514Arg variant results in a functionally impaired protein with ~50-60% activity, and that this variant may lead to aggregation of HNF1A within the cell [PMID: 27899486]. Additional studies are needed to confirm this in vitro finding and clinical correlation with moderately reduced functional impairment is needed. Based on the available evidence, the c.1541A>G p.(His514Arg) variant identified in the HNF1A gene is reported as a Variant of Uncertain Significance. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at