1-209789669-G-T

Variant names:

• chr1-209789669-G-T
• rs121434225
• NM_006147.4:c.1177C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP2 PP3

The NM_006147.4(IRF6):​c.1177C>A​(p.Gln393Lys) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000688 in 1,453,034 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: IRF6 NM_006147.4 missense, splice_region
• Scores: Splicing: ADA: 0.9674
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.11
• Publications: 0 publications found

Genes affected

IRF6 (HGNC:6121): (interferon regulatory factor 6) This gene encodes a member of the interferon regulatory transcription factor (IRF) family. Family members share a highly-conserved N-terminal helix-turn-helix DNA-binding domain and a less conserved C-terminal protein-binding domain. The encoded protein may be a transcriptional activator. Mutations in this gene can cause van der Woude syndrome and popliteal pterygium syndrome. Mutations in this gene are also associated with non-syndromic orofacial cleft type 6. Alternate splicing results in multiple transcript variants.[provided by RefSeq, May 2011]

IRF6 Gene-Disease associations (from GenCC):

• autosomal dominant popliteal pterygium syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae)
• IRF6-related condition

  Inheritance: AD Classification: DEFINITIVE Submitted by: Ambry Genetics
• van der Woude syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• popliteal pterygium syndrome

  Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics
• tooth agenesis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• van der Woude syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• orofacial cleft 6, susceptibility to

  Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ENSG00000289700 (HGNC:):

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_006147.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the IRF6 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 45 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: 2.7435 (below the threshold of 3.09). Trascript score misZ: 3.8897 (above the threshold of 3.09). GenCC associations: The gene is linked to van der Woude syndrome 1, van der Woude syndrome, autosomal dominant popliteal pterygium syndrome, orofacial cleft 6, susceptibility to, tooth agenesis, IRF6-related condition, popliteal pterygium syndrome.
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006147.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IRF6	NM_006147.4	MANE Select	c.1177C>A	p.Gln393Lys	missense splice_region	Exon 8 of 9	NP_006138.1
	IRF6	NM_001206696.2		c.892C>A	p.Gln298Lys	missense splice_region	Exon 6 of 7	NP_001193625.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IRF6	ENST00000367021.8	TSL:1 MANE Select	c.1177C>A	p.Gln393Lys	missense splice_region	Exon 8 of 9	ENSP00000355988.3
	ENSG00000289700	ENST00000696133.1		c.1177C>A	p.Gln393Lys	missense splice_region	Exon 8 of 10	ENSP00000512426.1
	IRF6	ENST00000542854.5	TSL:2	c.892C>A	p.Gln298Lys	missense splice_region	Exon 6 of 7	ENSP00000440532.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.88e-7 AC: 1 AN: 1453034 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 723530

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33282

American (AMR) AF: 0.00 AC: 0 AN: 44706

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26088

East Asian (EAS) AF: 0.00 AC: 0 AN: 39640

South Asian (SAS) AF: 0.00 AC: 0 AN: 86052

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53390

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 9.06e-7 AC: 1 AN: 1104024

Other (OTH) AF: 0.00 AC: 0 AN: 60094

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.39
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	D
Eigen	Pathogenic	0.84
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.56	D
MetaRNN	Pathogenic	0.91	D
MetaSVM	Uncertain	0.77	D
MutationAssessor	Benign	1.4	L
PhyloP100		9.1
PrimateAI	Pathogenic	0.79	T
PROVEAN	Uncertain	-2.8	D
REVEL	Pathogenic	0.81
Sift	Uncertain	0.0040	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.85
MutPred		0.72		Gain of methylation at Q393 (P = 0.0041)
MVP		0.96
MPC		1.9
ClinPred		1.0	D
GERP RS		6.0
Varity_R		0.72
gMVP		0.83
Mutation Taster		=50/50

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.97
dbscSNV1_RF	Pathogenic	0.83
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: rs121434225; hg19: chr1-209963014;