rs774283073

Positions:

chr8-63064311-T-C

Variant summary

Our verdict is Benign. Variant got -14 ACMG points: 0P and 14B. BP4_StrongBP6BP7BS1BS2

The NM_000370.3(TTPA):c.558A>G(p.Ser186=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000779 in 1,604,274 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000083 ( 2 hom. )

Consequence

TTPA
NM_000370.3 synonymous

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:2

Conservation

PhyloP100: 0.686

Variant links:

Genes affected

TTPA (HGNC:12404): (alpha tocopherol transfer protein) This gene encodes a soluble protein that binds alpha-trocopherol, a form of vitamin E, with high selectivity and affinity. This protein plays an important role in regulating vitamin E levels in the body by transporting vitamin E between membrane vesicles and facilitating the secretion of vitamin E from hepatocytes to circulating lipoproteins. Mutations in this gene cause hereditary vitamin E deficiency (ataxia with vitamin E deficiency, AVED) and retinitis pigmentosa. [provided by RefSeq, Nov 2009]

TTPA links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -14 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.54).

BP6

Variant 8-63064311-T-C is Benign according to our data. Variant chr8-63064311-T-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 586911.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Benign=1, Uncertain_significance=1}.

BP7

Synonymous conserved (PhyloP=0.686 with no splicing effect.

BS1

Variant frequency is greater than expected in population sas. gnomad4_exome allele frequency = 0.0000826 (120/1452138) while in subpopulation SAS AF= 0.00116 (99/85712). AF 95% confidence interval is 0.00097. There are 2 homozygotes in gnomad4_exome. There are 80 alleles in male gnomad4_exome subpopulation. Median coverage is 28. This position pass quality control queck.

BS2

High Homozygotes in GnomAdExome4 at 2 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TTPA	NM_000370.3 linkuse as main transcript	c.558A>G	p.Ser186=	synonymous_variant	4/5	ENST00000260116.5	NP_000361.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TTPA	ENST00000260116.5 linkuse as main transcript	c.558A>G	p.Ser186=	synonymous_variant	4/5	1	NM_000370.3	ENSP00000260116	P1
TTPA	ENST00000521138.1 linkuse as main transcript	n.233-15708A>G		intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152136

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000621

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000207

AC:

AN:

246398

Hom.:

AF XY:

0.000255

AC XY:

AN XY:

133444

show subpopulations

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:

0.00166

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.000166

GnomAD4 exome

AF:

0.0000826

AC:

120

AN:

1452138

Hom.:

Cov.:

AF XY:

0.000111

AC XY:

AN XY:

722846

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000225

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000253

Gnomad4 SAS exome

AF:

0.00116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000272

Gnomad4 OTH exome

AF:

0.000233

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152136

Hom.:

Cov.:

AF XY:

0.0000404

AC XY:

AN XY:

74308

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000621

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1Benign:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Benign:2

Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 12, 2024	- -
Likely benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Nov 13, 2017	- -

Familial isolated deficiency of vitamin E

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.54

CADD

Benign

8.7

DANN

Benign

0.75

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over