20-44419790-T-C

Position:

• chr20-44419790-T-C

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PP3 PP1_Moderate PP4_Moderate PM2_Supporting PS4

This summary comes from the ClinGen Evidence Repository: The c.740T>C variant in the hepatocyte nuclear factor 4-alpha gene, HNF4A, causes an amino acid change of leucine to proline at codon 247 (p.(Leu247Pro)) of NM_175914.5. This variant is absent in gnomAD v2.1.1 (PM2_Supporting) and is predicted to be deleterious by computational evidence, with a REVEL score of 0.979​, which is greater than the MDEP VCEP threshold of 0.70 (PP3). This variant was identified in seven unrelated individuals with non-autoimmune and non-absolute/near-absolute insulin-deficient diabetes (PS4; PMID:23771925, internal lab contributors). This variant was identified in an individual with a clinical history highly specific for HNF4A-monogenic diabetes (MODY probability calculator result >50%, negative genetic testing for HNF1A, and response to low-dose SU ) (PP4_Moderate; internal lab contributors). This variant was segregated with diabetes, with three informative meioses in two families (PP1_Moderate; internal lab contributors). In summary, c.733G>C meets the criteria to be classified as pathogenic for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP (specification version 2.0.0, approved 10/11/2023): PS4, PP1_moderate, PP3, PP4_moderate, PM2_Supporting. LINK:https://erepo.genome.network/evrepo/ui/classification/CA409107461/MONDO:0015967/085

• Frequency: Genomes: not found (cov: 32)
• Consequence: HNF4A NM_175914.5 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:2 U:1
• Conservation: PhyloP100: 8.01

Genes affected

HNF4A (HGNC:5024): (hepatocyte nuclear factor 4 alpha) The protein encoded by this gene is a nuclear transcription factor which binds DNA as a homodimer. The encoded protein controls the expression of several genes, including hepatocyte nuclear factor 1 alpha, a transcription factor which regulates the expression of several hepatic genes. This gene may play a role in development of the liver, kidney, and intestines. Mutations in this gene have been associated with monogenic autosomal dominant non-insulin-dependent diabetes mellitus type I. Alternative splicing of this gene results in multiple transcript variants encoding several different isoforms. [provided by RefSeq, Apr 2012]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PP1: For more information check the summary or visit ClinGen Evidence Repository.
• PP3: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HNF4A	NM_175914.5	c.740T>C	p.Leu247Pro	missense_variant	7/10	ENST00000316673.9	NP_787110.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HNF4A	ENST00000316673.9	c.740T>C	p.Leu247Pro	missense_variant	7/10	1	NM_175914.5	ENSP00000315180

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2 Uncertain:1

Revision: reviewed by expert panel

Submissions by phenotype

Monogenic diabetes Pathogenic:1

Pathogenic, reviewed by expert panel

curation

ClinGen Monogenic Diabetes Variant Curation Expert Panel

Aug 30, 2024

The c.740T>C variant in the hepatocyte nuclear factor 4-alpha gene, HNF4A, causes an amino acid change of leucine to proline at codon 247 (p.(Leu247Pro)) of NM_175914.5. This variant is absent in gnomAD v2.1.1 (PM2_Supporting) and is predicted to be deleterious by computational evidence, with a REVEL score of 0.979, which is greater than the MDEP VCEP threshold of 0.70 (PP3). This variant was identified in seven unrelated individuals with non-autoimmune and non-absolute/near-absolute insulin-deficient diabetes (PS4; PMID:23771925, internal lab contributors). This variant was identified in an individual with a clinical history highly specific for HNF4A-monogenic diabetes (MODY probability calculator result >50%, negative genetic testing for HNF1A, and response to low-dose SU ) (PP4_Moderate; internal lab contributors). This variant was segregated with diabetes, with three informative meioses in two families (PP1_Moderate; internal lab contributors). In summary, c.733G>C meets the criteria to be classified as pathogenic for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP (specification version 2.0.0, approved 10/11/2023): PS4, PP1_moderate, PP3, PP4_moderate, PM2_Supporting. -

Maturity-onset diabetes of the young type 1 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Apr 29, 2016

- -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jun 25, 2020

Not observed in large population cohorts (Lek et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Identified in one patient with maturity onset diabetes of the young, however, family segregation and functional studies were not performed; please note that this variant is reported using alternate nomenclature L260P (Pihoker et al., 2013); This variant is associated with the following publications: (PMID: 23771925) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	30
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.53	.;.;.;D;.;D;.
Eigen	Pathogenic	0.85
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Pathogenic	0.98	D;D;D;D;D;D;D
M_CAP	Pathogenic	0.87	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.1	.;.;.;.;H;H;H
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-5.8	D;.;D;.;D;D;D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D;.;D;.;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D;D
Polyphen		1.0	.;D;D;.;D;D;.
Vest4		0.99
MutPred		0.88		.;.;.;.;Loss of stability (P = 0.02);Loss of stability (P = 0.02);Loss of stability (P = 0.02);
MVP		0.99
MPC		1.3
ClinPred		1.0	D
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.98
gMVP		0.97

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs1555816654; hg19: chr20-43048430;