7-50382669-G-T

Variant names:

• chr7-50382669-G-T
• rs869312885
• NM_006060.6:c.551G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP2 PP3

The NM_006060.6(IKZF1):​c.551G>T​(p.Arg184Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic 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. R184W) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: IKZF1 NM_006060.6 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 10.0
• Publications: 0 publications found

Genes affected

IKZF1 (HGNC:13176): (IKAROS family zinc finger 1) This gene encodes a transcription factor that belongs to the family of zinc-finger DNA-binding proteins associated with chromatin remodeling. The expression of this protein is restricted to the fetal and adult hemo-lymphopoietic system, and it functions as a regulator of lymphocyte differentiation. Several alternatively spliced transcript variants encoding different isoforms have been described for this gene. Most isoforms share a common C-terminal domain, which contains two zinc finger motifs that are required for hetero- or homo-dimerization, and for interactions with other proteins. The isoforms, however, differ in the number of N-terminal zinc finger motifs that bind DNA and in nuclear localization signal presence, resulting in members with and without DNA-binding properties. Only a few isoforms contain the requisite three or more N-terminal zinc motifs that confer high affinity binding to a specific core DNA sequence element in the promoters of target genes. The non-DNA-binding isoforms are largely found in the cytoplasm, and are thought to function as dominant-negative factors. Overexpression of some dominant-negative isoforms have been associated with B-cell malignancies, such as acute lymphoblastic leukemia (ALL). [provided by RefSeq, May 2014]

IKZF1 Gene-Disease associations (from GenCC):

• pancytopenia due to IKZF1 mutations

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Illumina, Labcorp Genetics (formerly Invitae), Orphanet, ClinGen
• autoimmune disease

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 uncertain in NM_006060.6
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-50382668-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 827712.
• PP2: Missense variant in the IKZF1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 11 curated pathogenic missense variants (we use a threshold of 10). The gene has 3 curated benign missense variants. Gene score misZ: 3.3753 (above the threshold of 3.09). Trascript score misZ: 3.423 (above the threshold of 3.09). GenCC associations: The gene is linked to pancytopenia due to IKZF1 mutations, autoimmune disease.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.821

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006060.6. 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
	IKZF1	NM_006060.6	MANE Select	c.551G>T	p.Arg184Leu	missense	Exon 5 of 8	NP_006051.1
	IKZF1	NM_001410879.1		c.611G>T	p.Arg204Leu	missense	Exon 6 of 9	NP_001397808.1
	IKZF1	NM_001220765.3		c.551G>T	p.Arg184Leu	missense	Exon 5 of 7	NP_001207694.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IKZF1	ENST00000331340.8	TSL:1 MANE Select	c.551G>T	p.Arg184Leu	missense	Exon 5 of 8	ENSP00000331614.3
	IKZF1	ENST00000359197.9	TSL:1	c.551G>T	p.Arg184Leu	missense	Exon 5 of 7	ENSP00000352123.5
	IKZF1	ENST00000439701.2	TSL:1	c.551G>T	p.Arg184Leu	missense	Exon 5 of 7	ENSP00000413025.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1459218 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 725902

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44712

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86228

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51068

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5760

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111804

Other (OTH) AF: 0.00 AC: 0 AN: 60348

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.24
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.83	D
Eigen	Pathogenic	0.89
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.88	D
M_CAP	Uncertain	0.20	D
MetaRNN	Pathogenic	0.82	D
MetaSVM	Uncertain	-0.17	T
PhyloP100		10
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-6.3	D
REVEL	Uncertain	0.51
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.84
MutPred		0.54		Loss of disorder (P = 0.0508)
MVP		0.67
MPC		2.3
ClinPred		1.0	D
GERP RS		6.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2
Varity_R		0.73
gMVP		0.87
Mutation Taster		=28/72	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: rs869312885; hg19: chr7-50450367;