14-75902179-A-G

Position:

• chr14-75902179-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_015072.5(TTLL5):​c.3778A>G​(p.Ser1260Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000013 in 1,461,872 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S1260R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000013 (0 hom.)
• Consequence: TTLL5 NM_015072.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.21

Genes affected

TTLL5 (HGNC:19963): (tubulin tyrosine ligase like 5) This gene encodes a member of the tubulin tyrosine ligase like protein family. This protein interacts with two glucocorticoid receptor coactivators, transcriptional intermediary factor 2 and steroid receptor coactivator 1. This protein may function as a coregulator of glucocorticoid receptor mediated gene induction and repression. This protein may also function as an alpha tubulin polyglutamylase.[provided by RefSeq, Feb 2010]

IFT43 (HGNC:29669): (intraflagellar transport 43) This gene encodes a subunit of the intraflagellar transport complex A (IFT-A). IFT-A is a multiprotein complex that plays an important role in cilia assembly and maintenance by mediating retrograde ciliary transport. Mutations in this gene are a cause of cranioectodermal dysplasia-3 (CED3), also known as Sensenbrenner syndrome. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Dec 2011]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.07430932).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TTLL5	NM_015072.5	c.3778A>G	p.Ser1260Gly	missense_variant	31/32	ENST00000298832.14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TTLL5	ENST00000298832.14	c.3778A>G	p.Ser1260Gly	missense_variant	31/32	1	NM_015072.5	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251162 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135722

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: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000130 AC: 19 AN: 1461872 Hom.: 0 Cov.: 30 AF XY: 0.0000151 AC XY: 11 AN XY: 727240

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: 0.0000153

Gnomad4 OTH exome AF: 0.0000331

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000151

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 16, 2021

Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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. This variant has not been reported in the literature in individuals with TTLL5-related conditions. This variant is present in population databases (rs770500674, ExAC 0.001%). This sequence change replaces serine with glycine at codon 1260 of the TTLL5 protein (p.Ser1260Gly). The serine residue is weakly conserved and there is a small physicochemical difference between serine and glycine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.067
BayesDel_addAF	Benign	-0.22	T
BayesDel_noAF	Benign	-0.56
CADD	Benign	18
DANN	Benign	0.97
DEOGEN2	Benign	0.018	T
Eigen	Benign	-0.61
Eigen_PC	Benign	-0.47
FATHMM_MKL	Uncertain	0.81	D
LIST_S2	Benign	0.69	T
M_CAP	Benign	0.0060	T
MetaRNN	Benign	0.074	T
MetaSVM	Benign	-0.94	T
MutationAssessor	Benign	1.6	L
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.30	T
PROVEAN	Benign	-0.87	N
REVEL	Benign	0.086
Sift	Uncertain	0.0030	D
Sift4G	Benign	0.072	T
Polyphen		0.29	B
Vest4		0.23
MutPred		0.095		Gain of relative solvent accessibility (P = 0.0215);
MVP		0.088
MPC		0.080
ClinPred		0.16	T
GERP RS		3.1
Varity_R		0.11
gMVP		0.11

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.10		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: rs770500674; hg19: chr14-76368522;