chr4-16163413-G-C

Position:

• chr4-16163413-G-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_153365.3(TAPT1):​c.1599C>G​(p.Asp533Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,658 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. D533D) has been classified as Benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: TAPT1 NM_153365.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -1.02

Genes affected

TAPT1 (HGNC:26887): (transmembrane anterior posterior transformation 1) This gene encodes a highly conserved protein that localizes to the centrosome and/or ciliary basal body. Mutations in this gene disrupt Golgi morphology and trafficking and normal primary cilium formation and these mutations are congenitally manifested by severe undermineralization of the intra-uterine skeleton. A mutation in the mouse ortholog of this gene results in homeotic, posterior-to-anterior transformations of the axial skeleton which are similar to the phenotype of mouse homeobox C8 gene mutants. In mouse, this gene is thought to function downstream of homeobox C8 to transduce extracellular patterning information during axial skeleton development. [provided by RefSeq, Jan 2017]

TAPT1 (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.019039065).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TAPT1	NM_153365.3	c.1599C>G	p.Asp533Glu	missense_variant	14/14	ENST00000405303.7	NP_699196.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TAPT1	ENST00000405303.7	c.1599C>G	p.Asp533Glu	missense_variant	14/14	1	NM_153365.3	ENSP00000385347.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000802 AC: 2 AN: 249232 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135208

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000177

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461658 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727114

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: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Feb 08, 2022	In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The glutamic acid amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. This variant has not been reported in the literature in individuals affected with TAPT1-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.002%). This sequence change replaces aspartic acid, which is acidic and polar, with glutamic acid, which is acidic and polar, at codon 533 of the TAPT1 protein (p.Asp533Glu). -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Apr 13, 2022	Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.083
BayesDel_addAF	Benign	-0.34	T
BayesDel_noAF	Benign	-0.71
CADD	Benign	0.0070
DANN	Benign	0.85
DEOGEN2	Benign	0.026	T
Eigen	Benign	-1.5
Eigen_PC	Benign	-1.4
FATHMM_MKL	Benign	0.073	N
LIST_S2	Benign	0.72	T
M_CAP	Benign	0.0062	T
MetaRNN	Benign	0.019	T
MetaSVM	Benign	-0.97	T
MutationAssessor	Benign	-0.17	N
PrimateAI	Uncertain	0.49	T
PROVEAN	Benign	0.050	N
REVEL	Benign	0.16
Sift	Benign	0.37	T
Sift4G	Benign	1.0	T
Polyphen		0.013	B
Vest4		0.045
MutPred		0.12		Gain of methylation at K535 (P = 0.1103);
MVP		0.068
MPC		0.30
ClinPred		0.042	T
GERP RS		-6.4
Varity_R		0.039
gMVP		0.074

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs34007466; hg19: chr4-16165036;