12-120994229-C-T

Variant names:

• chr12-120994229-C-T
• rs886039544
• NM_000545.8:c.779C>T

Variant summary

Our verdict is Pathogenic. The variant received 15 ACMG points: 15P and 0B. PP1_Strong PM1_Supporting PS4 PP4_Moderate PM2_Supporting PS3_Moderate PP3

This summary comes from the ClinGen Evidence Repository: The c.779C>T variant in the HNF1 homeobox A gene, HNF1A, causes an amino acid change of threonine to methionine at codon 260 (p.(Thr260Met)) of NM_000545.8. This variant is located within a conserved region of the DNA binding domain (107-174 and 201-280) of HNF1A, which is defined as critical for the protein’s function by the ClinGen MDEP (PM1_Supporting). Additionally, variant is absent from gnomAD v2.1.1 (PM2_Supporting). This variant is predicted to be deleterious by computational evidence, with a REVEL score of 0.956, which is greater than the MDEP VCEP threshold of 0.70 (PP3). This variant was identified in at least 28 unrelated individuals with non- autoimmune and non-absolute/near-absolute insulin-deficient diabetes (PMIDs: 30760653, 29927023, 30663027, 29207974, 28105082, internal lab contributors). At least two of these individuals had a clinical history highly specific for HNF1A-MODY (MODY probability calculator result >50% and negative genetic testing for HNF4A, and both were antibody negative and one responded to low dose sulfonylureas) (PP4_Moderate; PMIDs: 30760653, 281505082). This variant segregated with diabetes, with 16 informative meioses in multiple families with MODY (PP1_Strong; PMIDs: 30760653. 28105082, internal lab contributors). A luciferase assay meeting the ClinGen MDEP quality control specifications demonstrated that the p.Thr260Met protein has transactivation activity below 40% of wildtype, indicating that this variant impacts protein function (PS3_Moderate; PMID:32910913). In summary, c.779C>T meets the criteria to be classified as pathogenic for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP (specification version 1.1, approved 9/30/2021): PM1_supporting, PM2_Supporting, PP3, PS4, PP4_Moderate, PP1_Strong, PS3_Moderate. LINK:https://erepo.genome.network/evrepo/ui/classification/CA10588543/MONDO:0015967/017

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: HNF1A NM_000545.8 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:8
• Conservation: PhyloP100: 7.49
• Publications: 29 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

Specifications for HNF1A are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Pathogenic. The variant received 15 ACMG points.

• PS3: For more information check the summary or visit ClinGen Evidence Repository.
• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM1: 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.

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.779C>T	p.Thr260Met	missense	Exon 4 of 10	NP_000536.6
	HNF1A	NM_001306179.2		c.779C>T	p.Thr260Met	missense	Exon 4 of 10	NP_001293108.2	F5H0K0
	HNF1A	NM_001406915.1		c.779C>T	p.Thr260Met	missense	Exon 4 of 9	NP_001393844.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	HNF1A	ENST00000257555.11	TSL:1 MANE Select	c.779C>T	p.Thr260Met	missense	Exon 4 of 10	ENSP00000257555.5	P20823-1
	HNF1A	ENST00000544413.2	TSL:1	c.779C>T	p.Thr260Met	missense	Exon 4 of 10	ENSP00000438804.1	F5H0K0
	HNF1A	ENST00000538646.5	TSL:1	n.592C>T		non_coding_transcript_exon	Exon 3 of 6	ENSP00000443964.1	P20823-4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000401 AC: 1 AN: 249268 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000546

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461240 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 726878

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44596

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26090

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39688

South Asian (SAS) AF: 0.00 AC: 0 AN: 86106

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53374

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111762

Other (OTH) AF: 0.0000166 AC: 1 AN: 60384

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
4	-	-	not provided (4)
3	-	-	Maturity-onset diabetes of the young (3)
1	-	-	Monogenic diabetes (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.92	D
Eigen	Pathogenic	0.73
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.91	D
M_CAP	Pathogenic	0.81	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	1.1	D
PhyloP100		7.5
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-4.6	D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.84		Gain of MoRF binding (P = 0.0811)
MVP		0.99
MPC		2.2
ClinPred		1.0	D
GERP RS		4.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
gMVP		0.93
Mutation Taster		=0/100	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs886039544; hg19: chr12-121432032; COSMIC: COSV57459458;