12-120997504-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_000545.8(HNF1A):c.1340C>G(p.Pro447Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,660 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 11/19 in silico tools predict a damaging outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P447L) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: HNF1A NM_000545.8 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.90

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 Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-120997504-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 14928.Status of the report is reviewed_by_expert_panel, 3 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
HNF1A	NM_000545.8	c.1340C>G	p.Pro447Arg	missense_variant	7/10	ENST00000257555.11
HNF1A	NM_001306179.2	c.1340C>G	p.Pro447Arg	missense_variant	7/10
HNF1A	XM_024449168.2	c.1340C>G	p.Pro447Arg	missense_variant	7/9
HNF1A	NM_001406915.1	c.1309+762C>G		intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
HNF1A	ENST00000257555.11	c.1340C>G	p.Pro447Arg	missense_variant	7/10	1	NM_000545.8	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459660 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726138

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.92
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
Cadd	Pathogenic	29
Dann	Uncertain	1.0
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D;D;D;D;D;D
M_CAP	Pathogenic	0.65	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-4.9	D;.;.;.;D;D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;.;.;.;D;D
Sift4G	Uncertain	0.0020	D;D;T;D;D;D
Polyphen		1.0	.;.;.;.;.;D
Vest4		0.98
MutPred		0.88		Gain of MoRF binding (P = 0.0046);Gain of MoRF binding (P = 0.0046);.;.;Gain of MoRF binding (P = 0.0046);Gain of MoRF binding (P = 0.0046);
MVP		0.99
MPC		0.50
ClinPred		1.0	D
GERP RS		4.5
gMVP		0.97

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs137853236; hg19: chr12-121435307;