NM_000545.8:c.-187C>T

Variant names:

• chr12-120978582-C-T
• rs970766228
• NM_000545.8:c.-187C>T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_000545.8(HNF1A):​c.-187C>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000615 in 650,100 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000060 (0 hom.)
• Consequence: HNF1A NM_000545.8 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance reviewed by expert panel U:1
• Conservation: PhyloP100: 1.21

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-AS1 (HGNC:26785): (HNF1A antisense RNA 1)

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.43).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HNF1A	NM_000545.8	c.-187C>T		5_prime_UTR_premature_start_codon_gain_variant	Exon 1 of 10	ENST00000257555.11	NP_000536.6
HNF1A	NM_000545.8	c.-187C>T		5_prime_UTR_variant	Exon 1 of 10	ENST00000257555.11	NP_000536.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HNF1A	ENST00000257555	c.-187C>T		5_prime_UTR_premature_start_codon_gain_variant	Exon 1 of 10	1	NM_000545.8	ENSP00000257555.5
HNF1A	ENST00000257555	c.-187C>T		5_prime_UTR_variant	Exon 1 of 10	1	NM_000545.8	ENSP00000257555.5

Frequencies

GnomAD3 genomes AF: 0.00000659 AC: 1 AN: 151828 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000242

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000113 AC: 1 AN: 88876 Hom.: 0 AF XY: 0.0000211 AC XY: 1 AN XY: 47346

Gnomad AFR exome AF: 0.000173

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000602 AC: 3 AN: 498272 Hom.: 0 Cov.: 4 AF XY: 0.00000749 AC XY: 2 AN XY: 266850

Gnomad4 AFR exome AF: 0.0000702

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: 0.00000680

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000659 AC: 1 AN: 151828 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74122

Gnomad4 AFR AF: 0.0000242

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000264

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: reviewed by expert panel

Submissions by phenotype

Monogenic diabetes Uncertain:1

Aug 18, 2021

ClinGen Monogenic Diabetes Variant Curation Expert Panel

Significance: Uncertain significance

Review Status: reviewed by expert panel

Collection Method: curation

The c.-187C>T variant in the HNF1 homeobox A gene, HNF1A, is a single nucleotide variant within the promoter of NM_000545.8. This variant is located within the API binding site (c.-187 to c.-195) of HNF1A, which is defined as critical for the protein’s function by the ClinGen MDEP (PM1_Supporting). While c.-187C>T is absent in the European non-Finnish population in gnomAD v2.1.1, it has 2 copies in the African subpopulation; therefore, this variant does not meet the ClinGen MDEP-established cutoff for PM2_Supporting. This variant was identified in 4 unrelated individuals with non- autoimmune and non-absolute/near-absolute insulin-deficient diabetes; however, PS4_Moderate cannot be applied because the variant does not meet the PM2_Supporting cutoff (internal lab contributors). One of these individuals has a clinical history highly specific for HNF1A-MODY (MODY probability calculator result >50%, negative genetic testing for HNF4A, and sulfonylurea sensitive) (PP4_Moderate; internal lab contributor). Taken together, this criteria supports the classification of c.-187C>T as a variant of uncertain significance for monogenic diabetes. ACMG/AMP criteria applied, as specified by the ClinGen MDEP VCEP (specification version 1.0, approved): PP4_moderate, PM1_Supporting. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.43
CADD	Benign	19
DANN	Benign	0.90
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.3

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

Publications

LitVar

Other links and lift over

dbSNP: rs970766228; hg19: chr12-121416385;