rs193922591

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_000545.8(HNF1A):​c.1854C>G​(p.Ile618Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000198 in 1,613,992 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000039 ( 1 hom., cov: 33)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

HNF1A
NM_000545.8 missense

Scores

1
6
11

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1O:1

Conservation

PhyloP100: -3.48

Publications

10 publications found
Variant links:
Genes affected
HNF1A (HGNC:11621): (HNF1 homeobox A) The protein encoded by this gene is a transcription factor required for the expression of several liver-specific genes. The encoded protein functions as a homodimer and binds to the inverted palindrome 5'-GTTAATNATTAAC-3'. Defects in this gene are a cause of maturity onset diabetes of the young type 3 (MODY3) and also can result in the appearance of hepatic adenomas. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Apr 2015]
C12orf43 (HGNC:25719): (chromosome 12 open reading frame 43) Predicted to be involved in Spemann organizer formation and negative regulation of Wnt signaling pathway. Predicted to be located in nuclear envelope. [provided by Alliance of Genome Resources, Apr 2022]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.20186967).
BS2
High AC in GnomAd4 at 6 AD,Unknown gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
HNF1ANM_000545.8 linkc.1854C>G p.Ile618Met missense_variant Exon 10 of 10 ENST00000257555.11 NP_000536.6
C12orf43NM_022895.3 linkc.*3003G>C 3_prime_UTR_variant Exon 6 of 6 ENST00000288757.7 NP_075046.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
HNF1AENST00000257555.11 linkc.1854C>G p.Ile618Met missense_variant Exon 10 of 10 1 NM_000545.8 ENSP00000257555.5
C12orf43ENST00000288757.7 linkc.*3003G>C 3_prime_UTR_variant Exon 6 of 6 1 NM_022895.3 ENSP00000288757.5

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152230
Hom.:
1
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000578
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.000956
GnomAD2 exomes
AF:
0.0000159
AC:
4
AN:
250950
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000218
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000178
AC:
26
AN:
1461762
Hom.:
0
Cov.:
34
AF XY:
0.0000151
AC XY:
11
AN XY:
727170
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44714
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.000176
AC:
7
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86250
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53352
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111974
Other (OTH)
AF:
0.000265
AC:
16
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
2
4
6
8
10
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152230
Hom.:
1
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74362
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41466
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000578
AC:
3
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68038
Other (OTH)
AF:
0.000956
AC:
2
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.463
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000264
Asia WGS
AF:
0.000577
AC:
2
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:1Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Jul 27, 2020
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 25, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 618 of the HNF1A protein (p.Ile618Met). This variant is present in population databases (rs193922591, gnomAD 0.03%). This missense change has been observed in individual(s) with clinical features of HNF1A-related conditions (PMID: 10588527, 32238361). ClinVar contains an entry for this variant (Variation ID: 36813). 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) has been performed at Invitae 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 HNF1A protein function. 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. -

not specified Uncertain:1Other:1
Sep 19, 2013
ITMI
Significance:not provided
Review Status:no classification provided
Collection Method:reference population

- -

Jul 07, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: HNF1A c.1854C>G (p.Ile618Met) results in a conservative amino acid change in the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change. The variant allele was found at a frequency of 1.6e-05 in 251050 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1854C>G has been observed in individuals affected with Maturity Onset Diabetes Of The Young (e.g., Ng_1999, Ma_2020). These data do not allow any conclusion about variant significance. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 10588527, 32238361). ClinVar contains an entry for this variant (Variation ID: 36813). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Diabetes mellitus type 1;C0011860:Type 2 diabetes mellitus;C1838100:Maturity-onset diabetes of the young type 3;C1840646:Hepatic adenomas, familial;C2675866:Type 1 diabetes mellitus 20;CN074294:Nonpapillary renal cell carcinoma Uncertain:1
Dec 29, 2023
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Maturity onset diabetes mellitus in young Uncertain:1
Feb 27, 2018
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.I618M variant (also known as c.1854C>G), located in coding exon 10 of the HNF1A gene, results from a C to G substitution at nucleotide position 1854. The isoleucine at codon 618 is replaced by methionine, an amino acid with highly similar properties. This variant was identified in an individual diagnosed with diabetes at age 38; his mother also had diabetes, but was not analyzed (Ng MC et al. Diabet. Med., 1999 Nov;16:956-63). This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on available evidence to date, the clinical significance of this alteration remains unclear. -

Ovarian cancer Benign:1
Jan 01, 2022
Laboratory of Molecular Epidemiology of Birth Defects, West China Second University Hospital, Sichuan University
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Uncertain
0.030
T
BayesDel_noAF
Uncertain
0.070
CADD
Benign
0.045
DANN
Benign
0.92
DEOGEN2
Uncertain
0.48
.;T;.;T;.
Eigen
Benign
-1.3
Eigen_PC
Benign
-1.5
FATHMM_MKL
Benign
0.096
N
LIST_S2
Benign
0.78
T;T;T;T;T
M_CAP
Pathogenic
0.32
D
MetaRNN
Benign
0.20
T;T;T;T;T
MetaSVM
Uncertain
0.62
D
PhyloP100
-3.5
PrimateAI
Uncertain
0.50
T
PROVEAN
Benign
-0.64
N;.;.;N;N
REVEL
Uncertain
0.57
Sift
Benign
0.067
T;.;.;T;T
Sift4G
Benign
0.16
T;T;D;T;T
Polyphen
0.90
.;.;.;.;P
Vest4
0.20
MutPred
0.75
.;.;.;.;Gain of catalytic residue at I625 (P = 0.0061);
MVP
0.97
MPC
0.57
ClinPred
0.61
D
GERP RS
-12
gMVP
0.89
Mutation Taster
=8/92
disease causing

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

Other links and lift over

dbSNP: rs193922591; hg19: chr12-121438953; API