chr12-120993519-G-A

Variant names:

• chr12-120993519-G-A
• rs1555211904
• NM_000545.8:c.527-1G>A

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PP1_Strong PS4_Moderate PVS1 PP4_Moderate PM2_Supporting

This summary comes from the ClinGen Evidence Repository: The c.527-1G>A variant in the HNF1 homeobox A gene, HNF1A, is predicted to remove a canonical splice acceptor site in intron 2 of NM_000545.8. This variant is predicted to cause skipping of biologically-relevant exon 3 of 10, resulting in a frameshift, leading to nonsense mediated decay in a gene in which loss-of-function is an established disease mechanism (PVS1; PMID:23348805). Also, this variant is absent from gnomAD v2.1.1 (PM2_Supporting). This variant was identified in 5 unrelated individuals with non- autoimmune and non-absolute/near-absolute insulin-deficient diabetes (PS4_Moderate; PMID:10588527, internal lab contributors). Additionally, this variant was identified in at least 2 individuals with a clinical history suggestive of HNF1A-MODY (MODY probability calculator result >50% and negative genetic testing for HNF4A), including one considered highly specific based on sulfonylurea-responsiveness (PP4_Moderate; internal lab contributors). This variant segregated with diabetes, with 7 informative meioses in 2 families with MODY (PP1_Strong; PMID:10588527, internal lab contributors). In summary, c.527-1G>A meets the criteria to be classified as pathogenic for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP (specification version 1.0, approved 9/30/2021): PVS1, PM2_Supporting, PS4_Moderate, PP4_Moderate, PP1_Strong. LINK:https://erepo.genome.network/evrepo/ui/classification/CA386963414/MONDO:0015967/017

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: HNF1A NM_000545.8 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic reviewed by expert panel P:7
• Conservation: PhyloP100: 9.44
• Publications: 0 publications found

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]

HNF1A Gene-Disease associations (from GenCC):

• monogenic diabetes

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• type 1 diabetes mellitus 20

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Laboratory for Molecular Medicine, Genomics England PanelApp
• diabetes mellitus, noninsulin-dependent

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• maturity-onset diabetes of the young type 3

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• hyperinsulinism due to HNF1A deficiency

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

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• nonpapillary renal cell carcinoma

  Inheritance: Unknown Classification: NO_KNOWN Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 17 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• 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.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000545.8. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HNF1A	NM_000545.8	MANE Select	c.527-1G>A		splice_acceptor intron	N/A	NP_000536.6
	HNF1A	NM_001306179.2		c.527-1G>A		splice_acceptor intron	N/A	NP_001293108.2	F5H0K0
	HNF1A	NM_001406915.1		c.527-1G>A		splice_acceptor intron	N/A	NP_001393844.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HNF1A	ENST00000257555.11	TSL:1 MANE Select	c.527-1G>A		splice_acceptor intron	N/A	ENSP00000257555.5	P20823-1
	HNF1A	ENST00000544413.2	TSL:1	c.527-1G>A		splice_acceptor intron	N/A	ENSP00000438804.1	F5H0K0
	HNF1A	ENST00000535955.5	TSL:1	n.43-3972G>A		intron	N/A

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461620 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 727108

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86234

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53334

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5748

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111902

Other (OTH) AF: 0.00 AC: 0 AN: 60374

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
3	-	-	not provided (3)
2	-	-	Maturity onset diabetes mellitus in young (2)
1	-	-	Maturity-onset diabetes of the young type 3 (1)
1	-	-	Monogenic diabetes (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.34
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	0.99
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		9.4
GERP RS		5.0
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.95
SpliceAI score (max)		0.94		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.37		Position offset: 3
DS_AL_spliceai		0.94		Position offset: 1

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

Other links and lift over

dbSNP: rs1555211904; hg19: chr12-121431322;