6-170561958-ACAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAG-ACAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAGCAG

Variant names:

• chr6-170561958-A-ACAGCAGCAGCAGCAGCAGCAGCAG
• rs752404282
• NM_003194.5:c.258_281dupGCAGCAGCAGCAGCAGCAGCAGCA

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BP3

The NM_003194.5(TBP):​c.258_281dupGCAGCAGCAGCAGCAGCAGCAGCA​(p.Gln87_Gln94dup) variant causes a disruptive inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000279 in 143,372 control chromosomes in the GnomAD database, with no homozygous occurrence. It is difficult to determine the true allele frequency of this variant because it is of type INS_BIG, and the frequency of such variant types in population databases may be underestimated and unreliable. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.000028 (0 hom., cov: 24)
  • Exomes 𝑓: 0.000013 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: TBP NM_003194.5 disruptive_inframe_insertion
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.290
• Publications: 4 publications found

Genes affected

TBP (HGNC:11588): (TATA-box binding protein) Initiation of transcription by RNA polymerase II requires the activities of more than 70 polypeptides. The protein that coordinates these activities is transcription factor IID (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 TBP, the TATA-binding protein. A distinctive feature of TBP is a long string of glutamines in the N-terminus. This region of the protein modulates the DNA binding activity of the C terminus, and modulation of DNA binding affects the rate of transcription complex formation and initiation of transcription. The number of CAG repeats encoding the polyglutamine tract is usually 25-42, and expansion of the number of repeats to 45-66 increases the length of the polyglutamine string and is associated with spinocerebellar ataxia 17, a neurodegenerative disorder classified as a polyglutamine disease. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2016]

TBP Gene-Disease associations (from GenCC):

• spinocerebellar ataxia type 17

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -1 ACMG points.

• BP3: Nonframeshift variant in repetitive region in NM_003194.5

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003194.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TBP	NM_003194.5	MANE Select	c.258_281dupGCAGCAGCAGCAGCAGCAGCAGCA	p.Gln87_Gln94dup	disruptive_inframe_insertion	Exon 3 of 8	NP_003185.1
	TBP	NM_001172085.2		c.198_221dupGCAGCAGCAGCAGCAGCAGCAGCA	p.Gln67_Gln74dup	disruptive_inframe_insertion	Exon 2 of 7	NP_001165556.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TBP	ENST00000392092.7	TSL:1 MANE Select	c.258_281dupGCAGCAGCAGCAGCAGCAGCAGCA	p.Gln87_Gln94dup	disruptive_inframe_insertion	Exon 3 of 8	ENSP00000375942.2
	TBP	ENST00000230354.10	TSL:1	c.258_281dupGCAGCAGCAGCAGCAGCAGCAGCA	p.Gln87_Gln94dup	disruptive_inframe_insertion	Exon 3 of 8	ENSP00000230354.5
	TBP	ENST00000421512.5	TSL:1	c.258_281dupGCAGCAGCAGCAGCAGCAGCAGCA	p.Gln87_Gln94dup	disruptive_inframe_insertion	Exon 3 of 5	ENSP00000400008.1

Frequencies

GnomAD3 genomes AF: 0.0000279 AC: 4 AN: 143372 Hom.: 0 Cov.: 24

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000683

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000216

Gnomad FIN AF: 0.000200

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.0000135 AC: 17 AN: 1261704 Hom.: 0 Cov.: 0 AF XY: 0.0000143 AC XY: 9 AN XY: 630696

African (AFR) AF: 0.00 AC: 0 AN: 28776

American (AMR) AF: 0.00 AC: 0 AN: 41894

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 23728

East Asian (EAS) AF: 0.00 AC: 0 AN: 38406

South Asian (SAS) AF: 0.0000612 AC: 5 AN: 81728

European-Finnish (FIN) AF: 0.0000215 AC: 1 AN: 46476

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4954

European-Non Finnish (NFE) AF: 0.0000106 AC: 10 AN: 941844

Other (OTH) AF: 0.0000186 AC: 1 AN: 53898

GnomAD4 genome AF: 0.0000279 AC: 4 AN: 143372 Hom.: 0 Cov.: 24 AF XY: 0.0000429 AC XY: 3 AN XY: 69954

African (AFR) AF: 0.00 AC: 0 AN: 39132

American (AMR) AF: 0.0000683 AC: 1 AN: 14642

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3200

East Asian (EAS) AF: 0.00 AC: 0 AN: 4928

South Asian (SAS) AF: 0.000216 AC: 1 AN: 4630

European-Finnish (FIN) AF: 0.000200 AC: 2 AN: 9992

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 290

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 63764

Other (OTH) AF: 0.00 AC: 0 AN: 1978

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.29
Mutation Taster		=54/46	polymorphism

Splicing

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

Other links and lift over

dbSNP: rs752404282; hg19: chr6-170871046;