chr7-100107509-C-CGGTG

Position:

• chr7-100107509-C-CGGTG

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_139315.3(TAF6):​c.1770_1771insCACC​(p.Ala591HisfsTer148) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. T590T) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TAF6 NM_139315.3 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -2.43

Genes affected

TAF6 (HGNC:11540): (TATA-box binding protein associated factor 6) 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 one of the smaller subunits of TFIID that binds weakly to TBP but strongly to TAF1, the largest subunit of TFIID. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jun 2010]

AP4M1 (HGNC:574): (adaptor related protein complex 4 subunit mu 1) This gene encodes a subunit of the heterotetrameric AP-4 complex. The encoded protein belongs to the adaptor complexes medium subunits family. This AP-4 complex is involved in the recognition and sorting of cargo proteins with tyrosine-based motifs from the trans-golgi network to the endosomal-lysosomal system. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.13 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TAF6	NM_139315.3	c.1770_1771insCACC	p.Ala591HisfsTer148	frameshift_variant	15/15	ENST00000453269.7
AP4M1	NM_004722.4	c.*629_*632dup		3_prime_UTR_variant	15/15	ENST00000359593.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TAF6	ENST00000453269.7	c.1770_1771insCACC	p.Ala591HisfsTer148	frameshift_variant	15/15	1	NM_139315.3	P1
AP4M1	ENST00000359593.9	c.*629_*632dup		3_prime_UTR_variant	15/15	1	NM_004722.4	P3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

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

Nov 15, 2021

Variant summary: TAF6 c.1767_1770dupCACC (p.Ala591HisfsX148) located in the last exon (exon 16) causes a frameshift which results in an extension of the protein. The variant was absent in 251006 control chromosomes. To our knowledge, no occurrence of c.1767_1770dupCACC in individuals affected with Alazami-Yuan Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Also, to our knowledge, no pathogenic variants downstream of the new stop codon have been reported. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. 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

No publications associated with this variant yet.

Other links and lift over

hg19: chr7-99705132;