2-27444494-C-A

Position:

• chr2-27444494-C-A

Variant summary

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

The NM_015662.3(IFT172):​c.5188G>T​(p.Val1730Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: IFT172 NM_015662.3 missense
• Clinical Significance: Uncertain significance no assertion criteria provided U:1
• Conservation: PhyloP100: 7.38

Genes affected

IFT172 (HGNC:30391): (intraflagellar transport 172) This gene encodes a subunit of the intraflagellar transport subcomplex IFT-B. Subcomplexes IFT-A and IFT-B are necessary for ciliary assembly and maintenance. Mutations in this gene have been associated with skeletal ciliopathies, with or without polydactyly, such as such short-rib thoracic dysplasias 1, 9 or 10. [provided by RefSeq, Mar 2014]

KRTCAP3 (HGNC:28943): (keratinocyte associated protein 3) Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IFT172	NM_015662.3	c.5188G>T	p.Val1730Leu	missense_variant	48/48	ENST00000260570.8	NP_056477.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IFT172	ENST00000260570.8	c.5188G>T	p.Val1730Leu	missense_variant	48/48	1	NM_015662.3	ENSP00000260570	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: no assertion criteria provided

Submissions by phenotype

IFT172-related disorder Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Jan 31, 2024

The IFT172 c.5188G>T variant is predicted to result in the amino acid substitution p.Val1730Leu. To our knowledge, this variant has not been reported in the literature or in a large population database, indicating this variant is rare. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.59
BayesDel_addAF	Uncertain	0.097	D
BayesDel_noAF	Benign	-0.10
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Benign	0.26	T
Eigen	Uncertain	0.59
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.92	D
M_CAP	Benign	0.037	D
MetaRNN	Uncertain	0.70	D
MetaSVM	Benign	-0.74	T
MutationAssessor	Uncertain	2.7	M
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.77	T
PROVEAN	Benign	-1.8	N
REVEL	Uncertain	0.30
Sift	Uncertain	0.013	D
Sift4G	Uncertain	0.022	D
Polyphen		1.0	D
Vest4		0.71
MutPred		0.39		Loss of ubiquitination at K1732 (P = 0.1202);
MVP		0.60
MPC		0.28
ClinPred		0.97	D
GERP RS		5.6
Varity_R		0.35
gMVP		0.72

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		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: rs985755052; hg19: chr2-27667361;