chr9-97687221-CCT-C

Position:

• chr9-97687221-CCT-C

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000380.4(XPA):​c.428_429del​(p.Glu143GlyfsTer11) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. E143E) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: XPA NM_000380.4 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 7.63

Genes affected

XPA (HGNC:12814): (XPA, DNA damage recognition and repair factor) This gene encodes a zinc finger protein plays a central role in nucleotide excision repair (NER), a specialized type of DNA repair. NER is responsible for repair of UV radiation-induced photoproducts and DNA adducts induced by chemical carcinogens and chemotherapeutic drugs. The encoded protein interacts with DNA and several NER proteins, acting as a scaffold to assemble the NER incision complex at sites of DNA damage. Mutations in this gene cause Xeroderma pigmentosum complementation group A (XP-A), an autosomal recessive skin disorder featuring hypersensitivity to sunlight and increased risk for skin cancer. [provided by RefSeq, Aug 2017]

ACMG classification

Verdict is Pathogenic. Variant got 18 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 9-97687221-CCT-C is Pathogenic according to our data. Variant chr9-97687221-CCT-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 555051.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
XPA	NM_000380.4	c.428_429del	p.Glu143GlyfsTer11	frameshift_variant	4/6	ENST00000375128.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
XPA	ENST00000375128.5	c.428_429del	p.Glu143GlyfsTer11	frameshift_variant	4/6	1	NM_000380.4	P1
XPA	ENST00000496104.1	n.222_223del		non_coding_transcript_exon_variant	3/4	3
XPA	ENST00000462523.5	c.428_429del	p.Glu143GlyfsTer11	frameshift_variant, NMD_transcript_variant	4/7	5

Frequencies

GnomAD3 genomes Cov.: 32

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

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Xeroderma pigmentosum group A Pathogenic:3

Pathogenic, criteria provided, single submitter	research	Kasturba Medical College, Manipal, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Nov 27, 2023	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Nov 15, 2017	- -

Xeroderma pigmentosum Pathogenic:1

Likely pathogenic, criteria provided, single submitter

curation

Sema4, Sema4

Nov 02, 2021

- -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 04, 2023

This premature translational stop signal has been observed in individual(s) with clinical features of xeroderma pigmentosum (PMID: 25566891). For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 555051). This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Glu143Glyfs*11) in the XPA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in XPA are known to be pathogenic (PMID: 27607234). -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.47		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.47		Position offset: 40

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

Publications

LitVar

Other links and lift over

dbSNP: rs1554701540; hg19: chr9-100449503;