<div class="infobox infobox-gene">
<table>
<tr><th colspan="2" style="background:#f0f0f0; text-align:center;">DCLRE1A</th></tr>
<tr><td><b>Full Name</b></td><td>DNA Cross-Link Repair 1A (SNM1A)</td></tr>
<tr><td><b>Chromosomal Location</b></td><td>10q26.3</td></tr>
<tr><td><b>NCBI Gene ID</b></td><td>[64421](https://www.ncbi.nlm.nih.gov/gene/64421)</td></tr>
<tr><td><b>OMIM</b></td><td>[607456](https://www.omim.org/entry/607456)</td></tr>
<tr><td><b>UniProt ID</b></td><td>[Q9H9Y6](https://www.uniprot.org/uniprotkb/Q9H9Y6/entry)</td></tr>
<tr><td><b>Protein Class</b></td><td>Metallo-beta-lactamase family nuclease</td></tr>
<tr><td><b>Expression</b></td><td>Ubiquitous, high in brain</td></tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">1 edges</a></td>
</tr>
</table>
</div>
The DCLRE1A gene (also known as SNM1A or DCLRE1A) encodes a member of the metallo-beta-lactamase superfamily of nucleases involved in DNA repair. This protein plays a critical role in resolving DNA interstrand crosslinks (ICLs), which are among the most cytotoxic forms of DNA damage. ICLs prevent DNA strand separation during replication and transcription, making their repair essential for cell survival[@moshous2007].
<div class="infobox infobox-gene">
<table>
<tr><th colspan="2" style="background:#f0f0f0; text-align:center;">DCLRE1A</th></tr>
<tr><td><b>Full Name</b></td><td>DNA Cross-Link Repair 1A (SNM1A)</td></tr>
<tr><td><b>Chromosomal Location</b></td><td>10q26.3</td></tr>
<tr><td><b>NCBI Gene ID</b></td><td>[64421](https://www.ncbi.nlm.nih.gov/gene/64421)</td></tr>
<tr><td><b>OMIM</b></td><td>[607456](https://www.omim.org/entry/607456)</td></tr>
<tr><td><b>UniProt ID</b></td><td>[Q9H9Y6](https://www.uniprot.org/uniprotkb/Q9H9Y6/entry)</td></tr>
<tr><td><b>Protein Class</b></td><td>Metallo-beta-lactamase family nuclease</td></tr>
<tr><td><b>Expression</b></td><td>Ubiquitous, high in brain</td></tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">1 edges</a></td>
</tr>
</table>
</div>
The DCLRE1A gene (also known as SNM1A or DCLRE1A) encodes a member of the metallo-beta-lactamase superfamily of nucleases involved in DNA repair. This protein plays a critical role in resolving DNA interstrand crosslinks (ICLs), which are among the most cytotoxic forms of DNA damage. ICLs prevent DNA strand separation during replication and transcription, making their repair essential for cell survival[@moshous2007].
DCLRE1A is particularly important in the central nervous system because neurons are post-mitotic cells that cannot rely on replication-coupled repair mechanisms. Instead, they depend heavily on transcription-coupled and global genome repair pathways to maintain genomic integrity over decades of lifespan[@fishel2009]. The inability to properly repair DNA damage in neurons is a hallmark of several neurodegenerative diseases, including [Alzheimer's disease](/diseases/alzheimers-disease) and [Parkinson's disease](/diseases/parkinsons-disease)[@shibata2020].
The DCLRE1A protein contains several key functional domains:
DCLRE1A functions as a 5' to 3' exo/endonuclease that can process DNA substrates in multiple ways:
DNA interstrand crosslinks are formed by endogenous metabolic products (such as aldehydes), environmental agents (such as chemotherapeutic agents like cisplatin), and certain chemotherapeutic drugs. The ICL repair pathway involves multiple proteins working in concert:
DCLRE1A's role in ICL repair makes it essential for maintaining genomic stability, particularly in tissues with high proliferative or metabolic activity[@demartin2007].
Beyond ICL repair, DCLRE1A contributes to transcription-coupled nucleotide excision repair (TC-NER), which removes bulky DNA adducts that block RNA polymerase II elongation. This pathway is especially important in neurons, where transcription-dependent repair is the primary mechanism for maintaining genomic integrity in actively transcribed genes[@mcgowan2008].
Multiple lines of evidence connect DCLRE1A dysfunction to [Alzheimer's disease](/diseases/alzheimers-disease) pathogenesis:
The metallo-beta-lactamase family to which DCLRE1A belongs has been implicated in the DNA repair deficits observed in AD brain. Altered expression or mutations in these proteins could contribute to the progressive genomic instability seen in affected neurons[@karakas2017].
In [Parkinson's disease](/diseases/parkinsons-disease), several mechanisms link DNA repair defects to neuronal death:
DCLRE1A and related nucleases may be affected by the same oxidative stress and mitochondrial dysfunction that drive PD pathogenesis[@shibata2020].
Mutations in DCLRE1A have been associated with a form of [hereditary spastic paraplegia](/diseases/hereditary-spastic-paraplegia) characterized by progressive lower limb spasticity and weakness. The precise mechanism by which DCLRE1A mutations cause HSP is under investigation, but likely involves defective DNA repair in corticospinal motor neurons.
DCLRE1A is expressed ubiquitously across human tissues, with particularly high expression in:
The protein localizes primarily to the nucleus, where it associates with chromatin. Some studies also report low-level cytoplasmic localization, which may be relevant for non-nuclear functions or for transport between cellular compartments.
Given the central role of DNA repair defects in neurodegeneration, several therapeutic strategies are being explored:
A major challenge in targeting DCLRE1A for neuroprotection is the need to enhance repair without promoting tumorigenesis. DNA repair proteins are often oncogenic when overexpressed or mutated, as they can allow cells with damaged DNA to survive and proliferate. Careful balancing of repair enhancement versus genomic stability is essential[@fouquerel2016].
The Moshous et al. study demonstrated that human SNM1A (DCLRE1A) is required for rad51-dependent homologous recombination, establishing its role in the ICL repair pathway[@moshous2007]. Subsequent studies showed that DCLRE1A forms a stable complex with RAD51 and is required for forming a functional RAD51 nucleoprotein filament[@demartin2007].
Madsen et al. provided a comprehensive review of DNA repair defects in aging and neurodegenerative disease, highlighting the importance of transcription-coupled repair in post-mitotic neurons[@madsen2011]. Studies in AD brain tissue demonstrated that multiple DNA repair pathways are compromised, including base excision repair, nucleotide excision repair, and double-strand break repair[@canugovi2012].
Recent work has focused on developing DNA repair-targeted interventions for neurodegeneration. Coppedè et al. reviewed pharmacological approaches to enhance DNA repair in neurons, including PARP inhibitors, Werner syndrome helicase modulators, and mitochondrial-targeted antioxidants[@coppede2022].
DCLRE1A interacts with several key DNA repair proteins:
Bioinformatic analysis reveals genetic interactions with:
Dclre1a knockout mice show embryonic lethality or severe developmental defects, underscoring the essential nature of this gene. Conditional knockouts in specific tissues have revealed tissue-specific requirements for ICL repair.
Primary neuronal cultures and neuronal cell lines have been used to study DCLRE1A function in the nervous system. These models demonstrate that DCLRE1A expression is induced in response to DNA damage and that knockdown increases sensitivity to DNA-damaging agents.
Several key questions remain about DCLRE1A function in the brain:
Answering these questions will require a combination of genomic, proteomic, and functional studies in model systems and human tissue[@sest2018].