rs886038346

Positions:

• chr12-120999314-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 1P and 0B. PM2_Supporting

This summary comes from the ClinGen Evidence Repository: The c.1548C>T variant in the HNF1 homeobox A gene, HNF1A, is a synonymous (silent) variant at codon 516 (p.(Gly516=)) of NM_000545.8. This variant has a minor allele frequency of 0.0000088 in the gnomAD v2.1.1 European non-Finnish population and no copies in another subpopulation, which is less than the ClinGen MDEP threshold for PM2_Supporting (≤0.00002 and ≤1 copy in any other subpopulation) (PM2_Supporting). BP7 was not applied for this synonymous variant because SpliceAI predicts an impact on splicing, specifically a gain of a novel splice acceptor site (score = 0.47); however, PP3 was not applied because an acceptor loss was not predicted (score = 0.03). In summary, c.1548C>T meets the criteria to be classified as a variant of uncertain significance for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP (specification version 1.1, approved 9/30/2021): PM2_Supporting. LINK:https://erepo.genome.network/evrepo/ui/classification/CA10587144/MONDO:0015967/017

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: HNF1A NM_000545.8 synonymous
• Clinical Significance: Uncertain significance reviewed by expert panel U:1 B:2
• Conservation: PhyloP100: 0.948

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HNF1A	NM_000545.8	c.1548C>T	p.Gly516=	synonymous_variant	8/10	ENST00000257555.11
HNF1A	NM_001306179.2	c.1548C>T	p.Gly516=	synonymous_variant	8/10
HNF1A	NM_001406915.1	c.1356C>T	p.Gly452=	synonymous_variant	7/9
HNF1A	XM_024449168.2	c.1548C>T	p.Gly516=	synonymous_variant	8/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HNF1A	ENST00000257555.11	c.1548C>T	p.Gly516=	synonymous_variant	8/10	1	NM_000545.8	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251184 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135850

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461676 Hom.: 0 Cov.: 57 AF XY: 0.00000138 AC XY: 1 AN XY: 727136

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1 Benign:2

Revision: reviewed by expert panel

Submissions by phenotype

Monogenic diabetes Uncertain:1

Uncertain significance, reviewed by expert panel

curation

ClinGen Monogenic Diabetes Variant Curation Expert Panel

May 02, 2022

The c.1548C>T variant in the HNF1 homeobox A gene, HNF1A, is a synonymous (silent) variant at codon 516 (p.(Gly516=)) of NM_000545.8. This variant has a minor allele frequency of 0.0000088 in the gnomAD v2.1.1 European non-Finnish population and no copies in another subpopulation, which is less than the ClinGen MDEP threshold for PM2_Supporting (less than or equal to 0.00002 and less than or equal to 1 copy in any other subpopulation) (PM2_Supporting). BP7 was not applied for this synonymous variant because SpliceAI predicts an impact on splicing, specifically a gain of a novel splice acceptor site (score = 0.47); however, PP3 was not applied because an acceptor loss was not predicted (score = 0.03). In summary, c.1548C>T meets the criteria to be classified as a variant of uncertain significance for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP (specification version 1.1, approved 9/30/2021): PM2_Supporting. -

not specified Benign:1

Likely benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

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- -

Maturity onset diabetes mellitus in young Benign:1

Likely benign, criteria provided, single submitter

research

Clinical Genomics, Uppaluri K&H Personalized Medicine Clinic

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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 rs886038346 with MODY3. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Benign	-0.076	T
BayesDel_noAF	Benign	-0.35
CADD	Benign	18
DANN	Benign	0.83
DEOGEN2	Benign	0.23	T
FATHMM_MKL	Benign	0.60	D
LIST_S2	Benign	0.50	T
MetaRNN	Benign	0.25	T
MutationTaster	Benign	1.0	D;D;D;D
Sift4G	Benign	0.061	T
Vest4		0.26
MVP		0.86
GERP RS		3.6

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.47		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.47		Position offset: 13

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

Publications

LitVar

Other links and lift over

dbSNP: rs886038346; hg19: chr12-121437117;