NM_175914.5:c.670+7C>A

Variant names:

• chr20-44418519-C-A
• rs376544046
• NM_175914.5:c.670+7C>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_175914.5(HNF4A):​c.670+7C>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000687 in 1,455,624 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: HNF4A NM_175914.5 splice_region, intron
• Scores: Splicing: ADA: 0.00002151
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.994
• Publications: 0 publications found

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]

HNF4A Gene-Disease associations (from GenCC):

• maturity-onset diabetes of the young type 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Ambry Genetics
• monogenic diabetes

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• diabetes mellitus, noninsulin-dependent

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• Fanconi renotubular syndrome 4 with maturity-onset diabetes of the young

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, G2P
• hyperinsulinism due to HNF4A deficiency

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• maturity-onset diabetes of the young

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.81).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_175914.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HNF4A	NM_175914.5	MANE Select	c.670+7C>A		splice_region intron	N/A	NP_787110.2
	HNF4A	NM_000457.6		c.736+7C>A		splice_region intron	N/A	NP_000448.3
	HNF4A	NM_001258355.2		c.715+7C>A		splice_region intron	N/A	NP_001245284.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HNF4A	ENST00000316673.9	TSL:1 MANE Select	c.670+7C>A		splice_region intron	N/A	ENSP00000315180.4
	HNF4A	ENST00000316099.10	TSL:1	c.736+7C>A		splice_region intron	N/A	ENSP00000312987.3
	HNF4A	ENST00000415691.2	TSL:1	c.736+7C>A		splice_region intron	N/A	ENSP00000412111.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 6.87e-7 AC: 1 AN: 1455624 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 724516

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33414

American (AMR) AF: 0.00 AC: 0 AN: 44712

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26104

East Asian (EAS) AF: 0.00 AC: 0 AN: 39680

South Asian (SAS) AF: 0.00 AC: 0 AN: 86190

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50314

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5754

European-Non Finnish (NFE) AF: 9.02e-7 AC: 1 AN: 1109208

Other (OTH) AF: 0.00 AC: 0 AN: 60248

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.81
CADD	Benign	0.16
DANN	Benign	0.73
PhyloP100		-0.99
RBP_binding_hub_radar		0.77
RBP_regulation_power_radar		2.1

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000022
dbscSNV1_RF	Benign	0.0
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

Other links and lift over

dbSNP: rs376544046; hg19: chr20-43047159;