3-129519147-C-A

Variant names:

• chr3-129519147-C-A
• NM_052989.3:c.3432C>A
• IFT122 p.Ile1144Ile

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_052989.3(IFT122):​c.3432C>A​(p.Ile1144Ile) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. I1144I) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: IFT122 NM_052989.3 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.0540
• Publications: 0 publications found

Genes affected

IFT122 (HGNC:13556): (intraflagellar transport 122) This gene encodes a member of the WD repeat protein family. WD repeats are minimally conserved regions of approximately 40 amino acids typically bracketed by gly-his and trp-asp (GH-WD), which may facilitate formation of heterotrimeric or multiprotein complexes. Members of this family are involved in a variety of cellular processes, including cell cycle progression, signal transduction, apoptosis, and gene regulation. This cytoplasmic protein contains seven WD repeats and an AF-2 domain which function by recruiting coregulatory molecules and in transcriptional activation. Mutations in this gene cause cranioectodermal dysplasia-1. A related pseudogene is located on chromosome 3. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jul 2013]

IFT122 Gene-Disease associations (from GenCC):

• cranioectodermal dysplasia 1

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, G2P
• cranioectodermal dysplasia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.55).
• BP7: Synonymous conserved (PhyloP=0.054 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_052989.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IFT122	NM_052989.3	MANE Select	c.3432C>A	p.Ile1144Ile	synonymous	Exon 28 of 30	NP_443715.1	Q9HBG6-1
	IFT122	NM_052985.4		c.3585C>A	p.Ile1195Ile	synonymous	Exon 29 of 31	NP_443711.2	Q9HBG6-5
	IFT122	NM_001410808.1		c.3435C>A	p.Ile1145Ile	synonymous	Exon 28 of 30	NP_001397737.1	A0A8I5KSG5

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IFT122	ENST00000348417.7	TSL:1 MANE Select	c.3432C>A	p.Ile1144Ile	synonymous	Exon 28 of 30	ENSP00000324005.4	Q9HBG6-1
	IFT122	ENST00000296266.7	TSL:1	c.3585C>A	p.Ile1195Ile	synonymous	Exon 29 of 31	ENSP00000296266.3	Q9HBG6-5
	IFT122	ENST00000507564.5	TSL:1	c.3411C>A	p.Ile1137Ile	synonymous	Exon 28 of 30	ENSP00000425536.1	Q9HBG6-6

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.55
CADD	Benign	5.4
DANN	Benign	0.58
PhyloP100		0.054
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		Details are displayed if max score is > 0.2

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr3-129237990;