rs746617574

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

The NM_000380.4(XPA):ā€‹c.555G>Cā€‹(p.Gln185His) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000821 in 1,608,286 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (ā˜…ā˜…).

Frequency

Genomes: š‘“ 0.000020 ( 0 hom., cov: 32)
Exomes š‘“: 0.000089 ( 0 hom. )

Consequence

XPA
NM_000380.4 missense, splice_region

Scores

11
7
1
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 7.52
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 9-97687096-C-G is Pathogenic according to our data. Variant chr9-97687096-C-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 550646.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
XPANM_000380.4 linkuse as main transcriptc.555G>C p.Gln185His missense_variant, splice_region_variant 4/6 ENST00000375128.5 NP_000371.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
XPAENST00000375128.5 linkuse as main transcriptc.555G>C p.Gln185His missense_variant, splice_region_variant 4/61 NM_000380.4 ENSP00000364270 P1
XPAENST00000496104.1 linkuse as main transcriptn.349G>C splice_region_variant, non_coding_transcript_exon_variant 3/43
XPAENST00000462523.5 linkuse as main transcriptc.555G>C p.Gln185His missense_variant, splice_region_variant, NMD_transcript_variant 4/75 ENSP00000433006

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152084
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000121
AC:
3
AN:
247850
Hom.:
0
AF XY:
0.0000149
AC XY:
2
AN XY:
133904
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000266
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000886
AC:
129
AN:
1456202
Hom.:
0
Cov.:
30
AF XY:
0.0000856
AC XY:
62
AN XY:
724090
show subpopulations
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:
0.000114
Gnomad4 OTH exome
AF:
0.0000332
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152084
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74282
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000441
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000565
Hom.:
0
Bravo
AF:
0.0000189
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Xeroderma pigmentosum group A Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsMar 12, 2024- -
Likely pathogenic, criteria provided, single submitterclinical testingCounsylFeb 07, 2017- -
XPA-related disorder Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingPreventionGenetics, part of Exact SciencesJun 13, 2023The XPA c.555G>C variant is predicted to result in the amino acid substitution p.Gln185His. This variant has been reported in the homozygous and compound heterozygous states in individuals with Xeroderma pigmentosum (Satokata et al. 1992. PubMed ID: 1372103; States et al. 1996. PubMed ID: 8765158). This variant is also at the last nucleotide of exon 4, which is part of the consensus splice site for this exon. Functional studies showed that this variant affects XPA function (Satokata et al. 1992. PubMed ID: 1372103; States et al. 1996. PubMed ID: 8765158; Nagel et al. 2014. PubMed ID: 24757057). This variant is reported in 0.0027% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/9-100449378-C-G). This variant is interpreted as likely pathogenic. -
Xeroderma pigmentosum Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpOct 18, 2022Variant summary: XPA c.555G>C (p.Gln185His) results in a non-conservative amino acid change located in the C-terminal domain (IPR022656) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. This variant also affects the last nucleotide of exon 4, and therefore could affect splicing: one computational tool predicts a significant impact on normal splicing, indicating that the variant abolishes a canonical 5' splicing donor site. Publications have reported experimental evidence confirming that this variant indeed affects mRNA splicing (e.g. Satokata_1992, States_1996, Nagel_2014).The variant allele was found at a frequency of 1.2e-05 in 247850 control chromosomes, exclusively within the European (non-Finnish) subpopulation (i.e. 3/112734 alleles) in the gnomAD database. c.555G>C has been reported in the literature in multiple homozygous and compound heterozygous individuals affected with Xeroderma pigmentosum, who were all of Caucasian ancestry, and generally had milder skin symptoms and absent or delayed-onset neurological disease (e.g. Satokata_1992, States_1996, States_1998). These data indicate that the variant is very likely to be associated with disease. Several publications reported experimental evidence evaluating the variant, and demonstrated that almost no correctly spliced mRNA was detected, and some mRNAs with in-frame insertions or deletions were also generated that theoretically could produce functional proteins (e.g. Satokata_1992, States_1996, Nagel_2014). This was consistent with a somewhat preserved UV-resistance of a patient-derived cell line that was homozygous for the variant of interest, and might also explain the milder clinical phenotypes reported in patients (Satokata_1992). Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Both laboratories classified the variant as likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
not provided Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpOct 26, 2023This sequence change affects codon 185 of the XPA mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the XPA protein. This variant also falls at the last nucleotide of exon 4, which is part of the consensus splice site for this exon. This variant is present in population databases (rs746617574, gnomAD 0.003%). This variant has been observed in individual(s) with clinical features of XPA-related conditions (PMID: 1372103). ClinVar contains an entry for this variant (Variation ID: 550646). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Experimental studies have shown that this variant affects XPA function (PMID: 24757057). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Studies have shown that this variant is associated with altered splicing resulting in multiple RNA products (PMID: 1372103). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.83
BayesDel_addAF
Pathogenic
0.32
D
BayesDel_noAF
Pathogenic
0.29
CADD
Pathogenic
33
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.85
D
Eigen
Pathogenic
0.69
Eigen_PC
Pathogenic
0.71
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.90
D
M_CAP
Uncertain
0.12
D
MetaRNN
Pathogenic
0.89
D
MetaSVM
Uncertain
-0.054
T
MutationAssessor
Pathogenic
3.3
M
MutationTaster
Benign
1.0
D
PrimateAI
Uncertain
0.61
T
PROVEAN
Pathogenic
-5.0
D
REVEL
Uncertain
0.64
Sift
Uncertain
0.029
D
Sift4G
Pathogenic
0.0
D
Polyphen
0.49
P
Vest4
0.90
MutPred
0.69
Loss of stability (P = 0.1207);
MVP
0.89
MPC
0.86
ClinPred
0.96
D
GERP RS
5.6
Varity_R
0.83
gMVP
0.81

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.96
SpliceAI score (max)
0.69
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.69
Position offset: 0

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs746617574; hg19: chr9-100449378; API