chr5-135028968-C-CG

Position:

• chr5-135028968-C-CG

Variant summary

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

The NM_002653.5(PITX1):​c.755_756insC​(p.Leu253AlafsTer319) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 34)
• Consequence: PITX1 NM_002653.5 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.34

Genes affected

PITX1 (HGNC:9004): (paired like homeodomain 1) This gene encodes a member of the RIEG/PITX homeobox family, which is in the bicoid class of homeodomain proteins. Members of this family are involved in organ development and left-right asymmetry. This protein acts as a transcriptional regulator involved in basal and hormone-regulated activity of prolactin. [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 0.201 CDS is truncated, and there are 1 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
PITX1	NM_002653.5	c.755_756insC	p.Leu253AlafsTer319	frameshift_variant	3/3	ENST00000265340.12
PITX1	XM_047417318.1	c.857_858insC	p.Leu287AlafsTer319	frameshift_variant	4/4
PITX1	XM_047417319.1	c.410_411insC	p.Leu138AlafsTer319	frameshift_variant	3/3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
PITX1	ENST00000265340.12	c.755_756insC	p.Leu253AlafsTer319	frameshift_variant	3/3	1	NM_002653.5	P1
PITX1	ENST00000506438.5	c.755_756insC	p.Leu253AlafsTer?	frameshift_variant	4/4	1		P1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 19, 2022

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. This variant has not been reported in the literature in individuals affected with PITX1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change results in a frameshift in the PITX1 gene (p.Leu253Alafs*319). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 62 amino acid(s) of the PITX1 protein and extend the protein by 256 additional amino acid residues. -

Computational scores

Source: dbNSFP v4.3

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr5-134364658;