chrX-71366294-CTGT-C

Variant names:

• chrX-71366294-CTGT-C
• rs779471221
• ENST00000373790:c.-76_-74delGTT

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The ENST00000373790(TAF1):​c.-76_-74delGTT variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000731 in 1,094,970 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 5 hemizygotes in GnomAD. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 19)
  • Exomes 𝑓: 0.0000073 (0 hom. 5 hem.)
• Consequence: TAF1 ENST00000373790 5_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.424

Genes affected

TAF1 (HGNC:11535): (TATA-box binding protein associated factor 1) Initiation of transcription by RNA polymerase II requires the activities of more than 70 polypeptides. The protein that coordinates these activities is the basal transcription factor TFIID, which binds to the core promoter to position the polymerase properly, serves as the scaffold for assembly of the remainder of the transcription complex, and acts as a channel for regulatory signals. TFIID is composed of the TATA-binding protein (TBP) and a group of evolutionarily conserved proteins known as TBP-associated factors or TAFs. TAFs may participate in basal transcription, serve as coactivators, function in promoter recognition or modify general transcription factors (GTFs) to facilitate complex assembly and transcription initiation. This gene encodes the largest subunit of TFIID. This subunit binds to core promoter sequences encompassing the transcription start site. It also binds to activators and other transcriptional regulators, and these interactions affect the rate of transcription initiation. This subunit contains two independent protein kinase domains at the N- and C-terminals, but also possesses acetyltransferase activity and can act as a ubiquitin-activating/conjugating enzyme. Mutations in this gene result in Dystonia 3, torsion, X-linked, a dystonia-parkinsonism disorder. Alternative splicing of this gene results in multiple transcript variants. This gene is part of a complex transcription unit (TAF1/DYT3), wherein some transcript variants share exons with TAF1 as well as additional downstream DYT3 exons. [provided by RefSeq, Oct 2013]

ACMG classification

Verdict is Likely_benign. Variant got -4 ACMG points.

• BS2: High Hemizygotes in GnomAdExome4 at 5 XL gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TAF1	NM_004606.5	c.-80_-78delTGT		upstream_gene_variant		ENST00000423759.6	NP_004597.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TAF1	ENST00000423759.6	c.-80_-78delTGT		upstream_gene_variant		5	NM_004606.5	ENSP00000406549.2

Frequencies

GnomAD3 genomes Cov.: 19

GnomAD3 exomes AF: 0.0000164 AC: 3 AN: 182885 Hom.: 0 AF XY: 0.0000296 AC XY: 2 AN XY: 67545

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000145

Gnomad SAS exome AF: 0.0000525

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000731 AC: 8 AN: 1094970 Hom.: 0 AF XY: 0.0000138 AC XY: 5 AN XY: 361294

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000997

Gnomad4 SAS exome AF: 0.0000185

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000476

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 19

Bravo AF: 0.0000264

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Dec 02, 2024

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: TAF1 c.-76_-74delGTT is located in the untranscribed region upstream of the TAF1 gene region. The variant allele was found at a frequency of 1.6e-05 in 182885 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.-76_-74delGTT in individuals affected with Mental Retardation, X-Linked, Syndromic 33 and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Splicing

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

Publications

LitVar

Other links and lift over

dbSNP: rs779471221; hg19: chrX-70586144;