2-172469137-C-T

Position:

• chr2-172469137-C-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000210.4(ITGA6):​c.400C>T​(p.Arg134*) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000274 in 1,461,832 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: ITGA6 NM_000210.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1 U:1
• Conservation: PhyloP100: 6.16

Genes affected

ITGA6 (HGNC:6142): (integrin subunit alpha 6) The gene encodes a member of the integrin alpha chain family of proteins. Integrins are heterodimeric integral membrane proteins composed of an alpha chain and a beta chain that function in cell surface adhesion and signaling. The encoded preproprotein is proteolytically processed to generate light and heavy chains that comprise the alpha 6 subunit. This subunit may associate with a beta 1 or beta 4 subunit to form an integrin that interacts with extracellular matrix proteins including members of the laminin family. The alpha 6 beta 4 integrin may promote tumorigenesis, while the alpha 6 beta 1 integrin may negatively regulate erbB2/HER2 signaling. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Oct 2015]

ITGA6 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-172469137-C-T is Pathogenic according to our data. Variant chr2-172469137-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 591460.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ITGA6	NM_001394928.1	c.400C>T	p.Arg134*	stop_gained	4/26	ENST00000442250.6	NP_001381857.1
ITGA6	NM_000210.4	c.400C>T	p.Arg134*	stop_gained	4/26	ENST00000684293.1	NP_000201.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ITGA6	ENST00000442250.6	c.400C>T	p.Arg134*	stop_gained	4/26	5	NM_001394928.1	ENSP00000406694.1
ITGA6	ENST00000684293.1	c.400C>T	p.Arg134*	stop_gained	4/26		NM_000210.4	ENSP00000508249.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461832 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727220

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1 Uncertain:1

Uncertain significance, no assertion criteria provided	research	Gharavi Laboratory, Columbia University	Sep 16, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Nov 22, 2023	This sequence change creates a premature translational stop signal (p.Arg134*) in the ITGA6 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in ITGA6 are known to be pathogenic (PMID: 9158140, 9185503, 9804362, 27607025). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ITGA6-related conditions. ClinVar contains an entry for this variant (Variation ID: 591460). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	40
DANN	Uncertain	1.0
Eigen	Pathogenic	0.84
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.99	D
Vest4		0.75, 0.79, 0.91, 0.79, 0.79
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.27		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.27		Position offset: -12

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

Publications

LitVar

Other links and lift over

dbSNP: rs866151033; hg19: chr2-173333865;