RPA1

Chr 17AD

replication protein A1

Also known as: HSSB, MST075, PFBMFT6, REPA1, RF-A, RP-A, RPA70

This gene encodes the largest subunit of the heterotrimeric Replication Protein A (RPA) complex, which binds to single-stranded DNA (ssDNA), forming a nucleoprotein complex that plays an important role in DNA metabolism, being involved in DNA replication, repair, recombination, telomere maintenance, and co-ordinating the cellular response to DNA damage through activation of the ataxia telangiectasia and Rad3-related protein (ATR) kinase. The nucleoprotein complex protects the single-stranded DNA from nucleases, prevents formation of secondary structures that would interfere with repair, and co-ordinates the recruitment and departure of different genome maintenance factors. This subunit contains four oligonucleotide/oligosaccharide-binding (OB) domains, though the majority of ssDNA binding occurs in two of these domains. The heterotrimeric complex has two different modes of ssDNA binding, a low-affinity and high-affinity mode, determined by which ssDNA binding domains are utilized. The different binding modes differ in the length of DNA bound and in the proteins with which it interacts, thereby playing a role in regulating different genomic maintenance pathways. [provided by RefSeq, Sep 2017]

GeneReviewsOMIMResearchGenerating clinical summary…
MultiplemechanismADLOEUF 0.431 OMIM phenotype
Clinical SummaryRPA1
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Gene-Disease Validity (ClinGen)
dyskeratosis congenita and related telomere biology disorder · ADLimited

Limited evidence — not for standalone diagnostic reporting

Population Constraint (gnomAD)
Constrained for loss-of-function variants (OE-LoF 0.25) despite low pLI — interpret in context.
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ClinVar Variants
2 unique Pathogenic / Likely Pathogenic· 72 VUS of 114 total submissions
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Clinical Trials
2 active or recruiting trials — potential therapeutic options may be available
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GeneReview available — RPA1
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Moderate LoF intolerance
LoF Constraint?
0.43LOEUF
pLI 0.088
Z-score 4.34
OE 0.25 (0.160.43)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint?
1.22Z-score
OE missense 0.82 (0.740.90)
292 obs / 356.7 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.25 (0.160.43)
00.351.4
Missense OE?0.82 (0.740.90)
00.61.4
Synonymous OE?1.01
01.21.6
LoF obs/exp: 10 / 39.4Missense obs/exp: 292 / 356.7Syn Z: -0.12

This gene — mechanism propensity

DN
0.6842th %ile
GOF
0.4874th %ile
LOF
0.3745th %ile

This gene has evidence for multiple mechanisms of pathogenicity (dominant-negative and gain-of-function). Both the Badonyi & Marsh prediction and the broader genomic evidence point to dominant-negative as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

DNprediction above median
GOF1 literature citation

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Literature Evidence

GOFGain-of-function mutations in RPA1 cause a syndrome with short telomeres and somatic genetic rescue.1

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

References

  1. 1.PMID 34767620

ClinVar Variant Classifications

114 submitted variants in ClinVar

Classification Summary

Pathogenic2
VUS72
Likely Benign7
Benign10
2
Pathogenic
72
VUS
7
Likely Benign
10
Benign

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
2
0
0
2
Likely Pathogenic
0
0
0
0
0
VUS
0
72
0
0
72
Likely Benign
0
3
0
4
7
Benign
0
1
5
4
10
Total0785891

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

72 pathogenic / likely-pathogenic (of 90) ClinVar copy-number / structural variants overlap RPA1 — these span large chromosomal regions, not the gene specifically, and are excluded from the counts above. Explore in CNV tools →

Protein Context — Lollipop Plot

RPA1 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.