rs1555211426

Variant names:

• chr12-120988940-C-T
• rs1555211426
• NM_000545.8:c.434C>T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PP1_Strong PS4_Moderate PM2_Supporting PP3 PM1

This summary comes from the ClinGen Evidence Repository: The c.434C>T variant in the HNF1 homeobox A gene, HNF1A, causes an amino acid change of serine to phenylalanine at codon 145 (p.(Ser145Phe)) of NM_000545.8. This variant was identified in six unrelated individuals with non- autoimmune and non-absolute/near-absolute insulin-deficient diabetes (PS4_Moderate; PMID:28701371, internal lab contributors). This variant segregated with diabetes, with 4 informative meioses in 2 families with MODY (PP1_Strong; PMID:28701371, internal lab contributors). This variant resides in an amino acid within the HNF1α DNA binding domain that directly binds DNA, which is defined as critical for the protein’s function by the ClinGen MDEP (PM1). This 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 0.989, which is greater than the MDEP threshold of 0.70 (PP3). Another missense variant, c.433T>C (p.(Ser145Pro)), has been classified as a VUS by the ClinGen MDEP; therefore, PM5 will not be applied. This variant was identified in at least six individuals with diabetes; however, the MODY probability is unable to be calculated due to lack of clinical information, and PP4 cannot be applied (PMID:28701371, internal lab contributors). In summary, c.434C>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 September 30, 2021): PP3, PM1, PM2_Supporting, PS4_Moderate, PP1_Strong. LINK:https://erepo.genome.network/evrepo/ui/classification/CA386959990/MONDO:0015967/017

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: HNF1A NM_000545.8 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:3
• Conservation: PhyloP100: 7.50
• 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 10 ACMG points.

• 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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HNF1A	NM_000545.8	c.434C>T	p.Ser145Phe	missense_variant	Exon 2 of 10	ENST00000257555.11	NP_000536.6
HNF1A	NM_001306179.2	c.434C>T	p.Ser145Phe	missense_variant	Exon 2 of 10		NP_001293108.2
HNF1A	NM_001406915.1	c.434C>T	p.Ser145Phe	missense_variant	Exon 2 of 9		NP_001393844.1
HNF1A	XM_024449168.2	c.434C>T	p.Ser145Phe	missense_variant	Exon 2 of 9		XP_024304936.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HNF1A	ENST00000257555.11	c.434C>T	p.Ser145Phe	missense_variant	Exon 2 of 10	1	NM_000545.8	ENSP00000257555.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461888 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727246

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

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: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: reviewed by expert panel

Submissions by phenotype

Maturity onset diabetes mellitus in young Pathogenic:1

-

Clinical Genomics, Uppaluri K&H Personalized Medicine Clinic

Significance: Likely risk allele

Review Status: criteria provided, single submitter

Collection Method: research

Mutations in HNF1A gene can predispose to MODY3. It is associated with both micro and macrovascular complications of diabetes, especially cardiovascular complications. Associated with glucosuria. May respond well to sulfonylureas. However, more evidence is required to confer the association of this particular variant rs1555211426 with MODY3. -

Monogenic diabetes Pathogenic:1

Apr 08, 2022

ClinGen Monogenic Diabetes Variant Curation Expert Panel

Significance: Pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

The c.434C>T variant in the HNF1 homeobox A gene, HNF1A, causes an amino acid change of serine to phenylalanine at codon 145 (p.(Ser145Phe)) of NM_000545.8. This variant was identified in six unrelated individuals with non- autoimmune and non-absolute/near-absolute insulin-deficient diabetes (PS4_Moderate; PMID: 28701371, internal lab contributors). This variant segregated with diabetes, with 4 informative meioses in 2 families with MODY (PP1_Strong; PMID: 28701371, internal lab contributors). This variant resides in an amino acid within the HNF1α DNA binding domain that directly binds DNA, which is defined as critical for the protein’s function by the ClinGen MDEP (PM1). This 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 0.989, which is greater than the MDEP threshold of 0.70 (PP3). Another missense variant, c.433T>C (p.(Ser145Pro)), has been classified as a VUS by the ClinGen MDEP; therefore, PM5 will not be applied. This variant was identified in at least six individuals with diabetes; however, the MODY probability is unable to be calculated due to lack of clinical information, and PP4 cannot be applied (PMID:28701371, internal lab contributors). In summary, c.434C>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 September 30, 2021): PP3, PM1, PM2_Supporting, PS4_Moderate, PP1_Strong. -

not provided Pathogenic:1

Nov 30, 2022

Athena Diagnostics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has been identified in multiple unrelated individuals with clinical features associated with this gene and appears to segregate with disease in at least one family (personal communication related to ClinVar ID 447489, lab code: 508240). This variant has not been reported in large, multi-ethnic general populations (http://gnomad.broadinstitute.org). The variant is located in a region that is considered important for protein function and/or structure. Computational tools predict that this variant is damaging. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.93	.;D;D;D;D;.
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.95	D;D;D;D;D;D
M_CAP	Pathogenic	0.93	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
PhyloP100		7.5
PrimateAI	Pathogenic	0.86	D
PROVEAN	Pathogenic	-5.7	D;.;.;.;D;D
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D;.;.;.;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D
Polyphen		1.0	.;.;.;.;.;D
Vest4		0.99
MutPred		0.88		Loss of disorder (P = 0.0045);Loss of disorder (P = 0.0045);Loss of disorder (P = 0.0045);Loss of disorder (P = 0.0045);Loss of disorder (P = 0.0045);Loss of disorder (P = 0.0045);
MVP		1.0
MPC		2.3
ClinPred		1.0	D
GERP RS		5.1
gMVP		0.99
Mutation Taster		=0/100	disease causing

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: rs1555211426; hg19: chr12-121426743;