22-19765450-C-A

Variant names:

• chr22-19765450-C-A
• rs2238773
• NM_001379200.1:c.868-308C>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001379200.1(TBX1):​c.868-308C>A variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,112 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: TBX1 NM_001379200.1 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.946
• Publications: 3 publications found

Genes affected

TBX1 (HGNC:11592): (T-box transcription factor 1) This gene is a member of a phylogenetically conserved family of genes that share a common DNA-binding domain, the T-box. T-box genes encode transcription factors involved in the regulation of developmental processes. This gene product shares 98% amino acid sequence identity with the mouse ortholog. DiGeorge syndrome (DGS)/velocardiofacial syndrome (VCFS), a common congenital disorder characterized by neural-crest-related developmental defects, has been associated with deletions of chromosome 22q11.2, where this gene has been mapped. Studies using mouse models of DiGeorge syndrome suggest a major role for this gene in the molecular etiology of DGS/VCFS. Several alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Jul 2008]

TBX1 Gene-Disease associations (from GenCC):

• conotruncal heart malformations

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• DiGeorge syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
• velocardiofacial syndrome

  Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics
• 22q11.2 deletion syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.85).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001379200.1. 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
	TBX1	NM_001379200.1	MANE Select	c.868-308C>A		intron	N/A	NP_001366129.1
	TBX1	NM_080647.1		c.841-308C>A		intron	N/A	NP_542378.1
	TBX1	NM_080646.2		c.841-308C>A		intron	N/A	NP_542377.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TBX1	ENST00000649276.2	MANE Select	c.868-308C>A		intron	N/A	ENSP00000497003.1
	TBX1	ENST00000332710.8	TSL:1	c.841-308C>A		intron	N/A	ENSP00000331791.4
	TBX1	ENST00000329705.11	TSL:1	c.841-308C>A		intron	N/A	ENSP00000331176.7

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152112 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152112 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74318

African (AFR) AF: 0.00 AC: 0 AN: 41462

American (AMR) AF: 0.0000654 AC: 1 AN: 15284

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5154

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10612

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 67986

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.85
CADD	Benign	4.4
DANN	Benign	0.35
PhyloP100		0.95

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs2238773; hg19: chr22-19752973;