20-44355854-G-T

Position:

• chr20-44355854-G-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_175914.5(HNF4A):​c.49+1G>T variant causes a splice donor change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 2/2 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: HNF4A NM_175914.5 splice_donor
• Scores: Splicing: ADA: 0.9034
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 5.86

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 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 3.3, offset of 41, new splice context is: gcgGTcagc. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 20-44355854-G-T is Pathogenic according to our data. Variant chr20-44355854-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 3062280.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HNF4A	NM_175914.5	c.49+1G>T		splice_donor_variant		ENST00000316673.9	NP_787110.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HNF4A	ENST00000316673.9	c.49+1G>T		splice_donor_variant		1	NM_175914.5	ENSP00000315180
HNF4A	ENST00000457232.5	c.49+1G>T		splice_donor_variant		1		ENSP00000396216
HNF4A	ENST00000609262.5	c.-183+1G>T		splice_donor_variant		1		ENSP00000476310
HNF4A	ENST00000609795.5	c.49+1G>T		splice_donor_variant		1		ENSP00000476609

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Likely pathogenic, criteria provided, single submitter

clinical testing

Molecular Genetics Department, Kulakov National Medical Research Center for Obstetrics, Gynecology and Perinatology

-

A previously undescribed nucleotide variant creates an alteration of the canonical splice site c.49+1G>T in the HNF4A gene. The variant was observed in heterozygous state in an individual affected with congenital hyperinsulinism. Loss-of-function variants are reported in patients with MODY, type I, 125850. The variant is not present in population database (gnomAD no frequency). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Uncertain	0.11
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Uncertain	0.34
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Uncertain	0.87	D
MutationTaster	Benign	1.0	D;D
GERP RS		5.2

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.90
dbscSNV1_RF	Benign	0.71

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr20-42984494;