MUTYH is involved in base excision repair (BER) with proliferating cell nuclear antigen (PCNA) in DNA replication, which is unique and critical for effective mutation-avoidance. It is also reported that MUTYH has a Zn-binding motif in a unique interdomain connector (IDC) region, which interacts with Rad9-Rad1-Hus1 complex (9-1 …The repair of a leaking Price Pfister faucet begins by shutting off the main water line. Insert a drain stopper to prevent smaller parts from falling off. Remove the faucet handle,...Base excision DNA repair involves a number of enzymes and protein cofactors that hasten repair of damaged DNA bases. Recent advances have identified macromolecular complexes that assemble at the DNA lesion and mediate repair. The repair of base lesions generally requires five enzymatic activities: glycosylase, endonuclease, …The base excision repair (BER) pathway is primary responsible for …Feb 6, 2567 BE ... Base Excision Repair - BER | DNA Damage & Repair Mechanism | Tamil | Molecular Biology |ThiNK VISION · Comments.Shake off the frustration of new iPhone update problems or other issues and take your iPhone in for repairs. Apple makes it easy to find an iPhone repair shop, whether or not your ...Updated: May 2003. In British Columbia, incidence of cancers of the head and neck region is 22.9/100,000 in males and 14.9/100,000 in females. Head and neck cancers are a heterogeneous group of tumours, consisting predominantly of squamous cancers of the lip, mouth, pharynx, larynx and cervical esophagus, adenocarcinomas of the major and …In contrast to UNG-mediated base excision initiation 6,7, we look to leverage on the cell’s innate base excision repair (BER) pathway, in which DNA polymerase β, DNA ligase III, and XRCC1 are ...Base excision repair (BER) is one of several DNA repair pathways found in all three domains of life. BER counters the mutagenic and cytotoxic effects of damage that occurs continuously to the nitrogenous bases in DNA, and its critical role in maintaining genomic integrity is well established. Howeve …Craniosynostosis repair is surgery to correct a problem that causes the bones of a child's skull to grow together (fuse) too early. Craniosynostosis repair is surgery to correct a ...The repair of UV-induced photodimers by long-patch BER is reminiscent of evolutionarily ancient pathways in bacteriophage and some bacteria and yeasts in which long-patch excision repair is triggered by a photodimer-specific DNA glycosylase or endonuclease such as T4 Endo V or UVDE. 3, 4, 30 Human cells appear to lack such …Jul 9, 2021 · Nucleotide excision repair refers to repair of DNA replication lesions or bulky adducts arising from distortions of the DNA structure. 3,200 Mismatch repair refers to adjustment of mismatched base ... The base excision repair (BER) pathway is a frontline defender of genomic integrity and plays a central role in epigenetic regulation through its involvement in the erasure of 5-methylcytosine. This biological and clinical significance has led to a demand for analytical methods capable of monitoring BER activities, especially in living cells. …May 29, 2020 · BER functions on different types of DNA base lesions that are generated by AID, TET and through oxidation. BER occurs in four mains steps that differ based on the mono/bifunctionality of the glycosylase: (i) base excision, (ii) DNA backbone incision, (iii) DNA end processing, (iv) repair of the lesion (5hmU, 5-hydroxymethyluracil; Tg, thymine ... Base excision repair (BER) is the major pathway for dealing with spontaneous, nonbulky forms of DNA damage, including simple oxidative and alkylation damage. These include base modifications (e.g., the common mutagenic 8-oxoguanine lesion), sites of base loss, and single-strand breaks in DNA. The most common oxidation product of DNA is base lesion 8-oxo-7,8-dihydroguanine (8-oxoG), which is repaired by 8-oxoG glycosylase1 (OGG1)-initiated baseexcision repair (BER) pathway (OGG1-BER); however, the role of OGG1-BER in oxidative stress-induced cell death is poorly investigated. DNA strand breaks and …Mar 1, 2017 · A representation of the base excision repair (BER) pathway for removing oxidative damage. (A) Classical BER cycle initiated by a monofunctional glycosylase and (B) a BER cycle started by a bifunctional glycosylase. The orange “P” represents a phosphate, -OH represents a 3′-hydroxyl and a 5′-2-deoxyribose-5-phosphate is represented by dRP. Abstract. Base excision repair (BER) and nucleotide excision repair (NER) are two DNA repair pathways that, like other DNA repair pathways except for direct reversal of DNA damage, involve sequential activities of multiple repair proteins. The two DNA repair pathways have been studied for more than four decades, and this investigation has ...DNA repair is a collection of several multienzyme, multistep processes keeping the cellular genome intact against genotoxic insults. One of these processes is base excision repair, which deals with the most ubiquitous lesions in DNA: oxidative base damage, alkylation, deamination, sites of base loss and single-strand breaks, etc. Individual enzymes acting …DNA repair is a collection of several multienzyme, multistep processes keeping the cellular genome intact against genotoxic insults. One of these processes is base excision repair, which deals with the most ubiquitous lesions in DNA: oxidative base damage, alkylation, deamination, sites of base loss and single-strand breaks, etc. Individual enzymes acting …Oct 9, 2023 · Gautam et al. show for the first time the existence of an alternative pathway to repair UV-induced DNA damage (photodimers) in normal human cells. This pathway functions additively but independently of NER and is human equivalent of the evolutionary-ancient base excision repair-dependent mechanism reported in bacteriophage and some bacteria. The goal of the present study was to investigate the relative contribution of the proposed mechanisms for cytotoxicity of 5-fluoropyrimidines. We demonstrate that in human cancer cells, base excision repair (BER) initiated by the uracil–DNA glycosylase UNG is the major route for FU–DNA repair in vitro and in vivo.Maintaining the chemical integrity of DNA in the face of assault by oxidizing agents is a constant challenge for living organisms. Base-excision repair has an important role in preventing ...Base-excision repair has an important role in preventing mutations associated with a common product of oxidative damage to DNA, 8-oxoguanine. Recent structural studies have shown that 8-oxoguanine ...ABSTRACT: The base excision repair (BER) pathway is a frontline defender of genomic integrity and plays a central role in epigenetic regulation through its involvement in the erasure of 5-methylcytosine. This biological and clinical significance has led to a demand for analytical methods capable of monitoring BER activities, especially in ...Beyond base excision repair: an evolving picture of mitochondrial DNA repair. 2021 Oct 29;41 (10):BSR20211320. doi: 10.1042/BSR20211320. Formerly: Solent University Southampton, East Park Terrace, Southampton, SO14 0YN, UK. School of Natural and Social Sciences, University of Gloucestershire, Francis Close Hall, Swindon …Base excision repair is a highly conserved mechanism dealing with …Base excision repair system targeting DNA adducts of trioxacarcin/LL-D49194 antibiotics for self-resistance Nucleic Acids Res. 2022 Mar 21 ... (AP) sites generated from TxnU4 excision of intercalated TXNA-DNA adducts are incised by AP endonuclease less efficiently than those formed by 7mG excision. This work …DNA base damage (including deamination, oxidation, or alkylation) is repaired through base excision repair (BER) pathway, which is highly conserved in pro- and eukaryotes [].To date, BER is believed to be the simplest, thoroughly characterized process among all DNA repair pathways [2, 3].BER is initiated by mono- or bi-functional DNA …Base excision repair. Base excision repair (BER) is one of the most important DNA repair pathways, which ameliorates environmentally induced DNA damage, including that which arises spontaneously as a result of alkylation, oxidation, and deamination events during normal metabolic processes [].BER is also responsible for …Base excision repair (BER) is the predominant DNA damage repair pathway for the processing of small base lesions, derived from oxidation and alkylation damages. BER is normally defined as DNA repair initiated by lesion-specific DNA glycosylases and completed by either of the two sub-pathways: short-patch BER where only one …Three types of excision repair—base-excision repair, nucleotide-excision repair, and mismatch repair—enable cells to cope with a variety of different kinds of DNA damage. The repair of uracil-containing DNA is a good example of base-excision repair, in which single damaged bases are recognized and removed from the DNA molecule (Figure 5.23). An excision repair refers to the DNA repair mechanism that deals with the damaged …Jul 25, 2023 · Base excision repair works by excising a single damaged base or nucleotide; this is under the mediation of DNA glycosylases cutting the bond between the nitrogenous base and the deoxyribose sugars. When the glycosylases remove the base, it creates an apurinic site if the removed base was a purine (adenine, guanine), or an apyrimidinic site if ... Three types of excision repair—base-excision repair, nucleotide-excision repair, and mismatch repair—enable cells to cope with a variety of different kinds of DNA damage. The repair of uracil-containing DNA is a good example of base-excision repair, in which single damaged bases are recognized and removed from the DNA molecule (Figure 5.23). Jun 12, 2557 BE ... 166-Mismatch & Base Excision Repair. Fundamentals of Biochemistry•22K ... 167-Nucleotide Excision Repair; Double Strand Breaks. Fundamentals of ...Keywords: inter-strand DNA crosslink, bulky DNA adduct, base excision repair, DNA glycosylase, nucleotide excision repair, Fanconi anemia Citation: Baiken Y, Kanayeva D, Taipakova S, Groisman R, Ishchenko AA, Begimbetova D, Matkarimov B and Saparbaev M (2021) Role of Base Excision Repair Pathway in the Processing of …In higher eukaryotes, base excision repair can proceed by two alternative pathways: a DNA polymerase beta-dependent pathway and a proliferating cell nuclear antigen (PCNA)-dependent pathway. Recently, we have reconstituted the PCNA-dependent AP site repair reaction with six purified human proteins: …Oct 23, 2561 BE ... Nucleotide excision repair and base excision repair - This DNA repair lecture explains about the difference between nucleotide excision ...Base excision repair (BER) is probably the most frequently used DNA repair mode in nature. In this pathway, the excision of base damage is initiated by the action of a class of DNA repair enzymes called DNA glycosylases. The initial enzymatic event during BER forms sites in DNA without a base, called apurinic, apyrimidinic, or …Jul 31, 2562 BE ... ... excision de base (ou BER pour Base excision repair en anglais) est l'un des mécanismes de réparation de l'ADN utilisé par les cellules ...The base excision repair (BER) pathway is a critical DNA repair mechanism for removal of damaged bases arising from oxidation, alkylation, or deamination (Krokan and Bjoras, 2013). BER is initiated by DNA glycosylases that excise the damaged base and completed by additional proteins that remove the remaining sugar–phosphate …This detailed volume provides a comprehensive set of experimental protocols and useful strategies to examine the repair of damaged bases via the Base Excision Repair (BER) pathway in vitro and in cells. Beginning with multiple molecular and cellular techniques to examine the excision of damaged bases from double-stranded DNA or DNA wrapped in a ... The base excision repair (BER) pathway functions to repair single-base DNA lesions and in the process creates the premutagenic apurinic/apyrimidinic (AP) sites. In this review, we discuss the components of the BER pathway in the nematode Caenorhabditis elegans and delineate the different phenotypes caused by the deletion …To counteract DNA base damage, cells have evolved several defense mechanisms that act at different levels to prevent or repair DNA base damage. Cells combat genomic lesions like these including base modifications, abasic sites, as well as single-strand breaks, via the base excision repair (BER) pathway.Nucleotide Excision Repair. The nucleotide excision repair (NER) pathway is a DNA repair mechanism whose principle function is to remove helically distorting DNA lesions prior to synthesis of new DNA to reduce the mutagenic risk these lesions possess. From: Advances in Protein Chemistry and Structural Biology, 2019. Related terms: Base Excision ... Further, depletion of the base excision repair (BER) enzyme DNA glycosylase augments PD-L1 upregulation in response to H 2 O 2. PD-L1 upregulation in BER-depleted cells requires ATR/Chk1 kinase ...Jun 12, 2557 BE ... Review of the processes and components of repair of mismatched DNA and of damages bases in DNA.2024-02-01. Description. Of the three major pathways involved in the repair of nucleotide damage in DNA, base excision repair (BER) involves the greatest number of individual enzymatic activities. This is the consequence of the numerous individual glycosylases, each of which recognizes and removes a specific modified base (s) from …The base excision repair (BER) pathway is a critical DNA repair mechanism for removal of damaged bases arising from oxidation, alkylation, or deamination (Krokan and Bjoras, 2013). BER is initiated by DNA glycosylases that excise the damaged base and completed by additional proteins that remove the remaining sugar–phosphate …Base excision repair (BER) corrects DNA damage from oxidation, deamination and alkylation. Such base lesions cause little distortion to the DNA helix structure. BER is initiated by a DNA glycosylase that recognizes and removes the damaged base, leaving an abasic site that is further processed by short-patch repair or long-patch repair that ... To counteract DNA base damage, cells have evolved several defense mechanisms that act at different levels to prevent or repair DNA base damage. Cells combat genomic lesions like these including base modifications, abasic sites, as well as single-strand breaks, via the base excision repair (BER) pathway. Understanding of BRCA1/2 interaction with the base excision repair (BER) pathway could improve therapy based on ‘synthetic lethality’, whose effectiveness is based on homologous recombination ...Nov 16, 2020 · This protocol describes a comet-based in vitro assay for detecting base and nucleotide excision repair activity for use in cell culture model systems, human biomonitoring and clinical ... Base excision DNA repair (BER) is a key pathway safeguarding the genome of all living organisms from damage caused by both intrinsic and environmental factors. Most present knowledge about BER comes from studies of human cells, E. coli, and yeast. Plants may be under an even heavier DNA damage threat from abiotic stress, …In contrast to UNG-mediated base excision initiation 6,7, we look to leverage on the cell’s innate base excision repair (BER) pathway, in which DNA polymerase β, DNA ligase III, and XRCC1 are ...The negative selective pressure imposed by lesion nucleobases has driven the evolution of repair pathways dedicated to recognition and removal of base lesions, followed by restoration of the original DNA sequence-(Lindahl, 1993).The major pathway for this type of repair (Fig. 1) is initiated by the excision of a damaged base and is therefore known …Although a majority of the TMZ-induced lesions (N7-methylguanine and N3-methyladenine) are base excision repair (BER) substrates, these DNA lesions are also readily repaired. However, blocking BER can enhance response to TMZ and therefore the BER pathway has emerged as an attractive target for reversing TMZ resistance.A representation of the base excision repair (BER) pathway for removing oxidative damage. (A) Classical BER cycle initiated by a monofunctional glycosylase and (B) a BER cycle started by a bifunctional glycosylase. The orange “P” represents a phosphate, -OH represents a 3′-hydroxyl and a 5′-2-deoxyribose-5-phosphate is represented by dRP.Aug 30, 2017 · Base excision repair (BER) is the cell’s primary response to G:U mismatches and is initiated by excision of the uracil by uracil N-glycosylase (UNG) . In an effort to protect the edited G:U intermediate from excision by UNG, we fused a 83–amino acid uracil glycosylase inhibitor (UGI) directly to the C terminus of catalytically dead Cas9 ... Create publication-quality figures from editable icons and templates, with BioRender's scientific illustration software.In contrast to UNG-mediated base excision initiation 6,7, we look to leverage on the cell’s innate base excision repair (BER) pathway, in which DNA polymerase β, DNA ligase III, and XRCC1 are ...Base excision repair (BER) is a critical genome defense pathway that deals with a broad range of non-voluminous DNA lesions induced by endogenous or exogenous genotoxic agents. BER is a complex process initiated by the excision of the damaged base, proceeds through a sequence of reactions that generate various DNA intermediates, and …Dec 12, 2012 · Base excision repair is the system used from bacteria to man to remove the tens of thousands of endogenous DNA damages produced daily in each human cell. Base excision repair is required for normal mammalian development and defects have been associated with neurological disorders and cancer. In this paper we provide an overview of short patch ... May 2, 2016 · Base excision repair (BER) is an essential DNA repair pathway involved in the maintenance of genome stability and thus in the prevention of human diseases, such as premature aging, neurodegenerative diseases, and cancer. Protein posttranslational modifications (PTMs), including acetylation, methylation, phosphorylation, SUMOylation, and ... DNA ligase I (LIG1) catalyzes the ligation of the nick repair intermediate after gap filling by DNA polymerase (pol) β during downstream steps of the base excision repair (BER) pathway. However ...The Cost of Skin Tag Removal. The cost of skin tag removal is dependent on the …In today’s fast-paced and technology-driven world, businesses are constantly looking for ways to streamline their operations and maximize efficiency. One area that often gets overl...Lamin A/C promotes base excision repair of oxidative lesions. Studies suggest that lamins have a role in regulating cell proliferation , including as a component of the oxidative DDR . Thus, our early investigations into the role of lamin A/C in genome maintenance involved comparing cellular proliferation of Lmna −/− MEFs with Lmna +/+ …Craniosynostosis repair is surgery to correct a problem that causes the bones of a child's skull to grow together (fuse) too early. Craniosynostosis repair is surgery to correct a ...Dec 15, 2007 · The correction of exogenous and endogenous environmental insult to DNA involves a series of DNA repair mechanisms that reduce the likelihood of mutation accumulation and hence an increased probability of tumour development. The mechanisms underlying the process of base excision repair are relatively well understood and are placed in context with how deterioration of this process is associated ... 塩基除去修復. 塩基除去修復 （えんきじょきょしゅうふく、base excision repair）は、生体に備わっている DNA修復機構 の1つで、 DNA を構成する 塩基 の損傷を修復する。. 省略してBERと呼ばれる。. DNAを構成する塩基は恒常的に活性酸素種やアルキル化剤、また ... During base excision repair (BER), the apurinic or apyrimidinic (AP) site …May 15, 2022 · Excision Repair, in which the damaged base or bases are removed and then replaced with the correct ones in a localized burst of DNA synthesis. There are three modes of excision repair, each of which employs specialized sets of enzymes. Base Excision Repair ( BER) Nucleotide Excision Repair ( NER) Mismatch Repair ( MMR) Base excision repair (BER) corrects small base lesions that do not significantly distort the DNA helix structure. Such damage typically results from deamination, oxidation, or methylation ().Much of the damage is the result of spontaneous decay of DNA (Lindahl 1993), although similar damage may also be caused by environmental chemicals, …Advertisement Electric ranges and ovens are generally easy to repair, because there's not much to go wrong and there's not much you can do. Most repairs are actually replacements, ...Understanding of BRCA1/2 interaction with the base excision repair (BER) pathway could improve therapy based on ‘synthetic lethality’, whose effectiveness is based on homologous recombination ...Two forms of DNA base excision-repair (BER) have been observed: a 'short-patch' BER pathway involving replacement of one nucleotide and a 'long-patch' BER pathway with gap-filling of several nucleotides. The latter mode of repair has been investigated using human cell-free extracts or purified proteins.Excision repair The most common means of repairing damage or a mismatch is to cut it out of the duplex DNA and recopy the remaining complementary strand of DNA, as outlined in Fig. 7.12. Three different types of excision repair have been characterized: nucleotide excision repair, base excision repair, and mismatch repair. Of the three major pathways involved in the repair of nucleotide damage in DNA, base excision repair (BER) involves the greatest number of individual enzymatic activities. This is the consequence of the numerous individual glycosylases, each of which recognizes and removes a specific modified base(s) from DNA.Base excision repair (BER) corrects DNA damage from oxidation, deamination and alkylation. Such base lesions cause little distortion to the DNA helix structure. BER is initiated by a DNA glycosylase that recognizes and removes the damaged base, leaving an abasic site that is further processed by short-patch repair or long-patch repair that ... Base excision repair (BER) removes and replaces damaged or non …The repair of UV-induced photodimers by long-patch BER is reminiscent of evolutionarily ancient pathways in bacteriophage and some bacteria and yeasts in which long-patch excision repair is triggered by a photodimer-specific DNA glycosylase or endonuclease such as T4 Endo V or UVDE. 3, 4, 30 Human cells appear to lack such …Dec 12, 2012 · Base excision repair is the system used from bacteria to man to remove the tens of thousands of endogenous DNA damages produced daily in each human cell. Base excision repair is required for normal mammalian development and defects have been associated with neurological disorders and cancer. In this paper we provide an overview of short patch ... Base excision repair (BER) is one of several DNA repair pathways found in all three domains of life. BER counters the mutagenic and cytotoxic effects of damage that occurs continuously to the nitrogenous bases in DNA, and its critical role in maintaining genomic integrity is well established. Howeve …The repair of UV-induced photodimers by long-patch BER is reminiscent of evolutionarily ancient pathways in bacteriophage and some bacteria and yeasts in which long-patch excision repair is triggered by a photodimer-specific DNA glycosylase or endonuclease such as T4 Endo V or UVDE. 3, 4, 30 Human cells appear to lack such …In mitochondria, base excision repair (BER) is the most characterized mechanism to counteract the prominent generation of oxidized bases within mtDNA. Although mitochondria are considered to be devoid of nucleotide excision repair (NER), proteins involved in nuclear NER localize within the mitochondria ( 80–83 ) and are …
Base excision repair overview. Base excision repair (BER) is a highly conserved pathway from bacteria to humans and is responsible for repairing the vast majority of endogenous DNA damage including alkylations, oxidations, deaminations and depurinations, as well as single-strand breaks (SSBs) (for reviews see [ 1, 2 ]. . Cuddl duds socks
The estimated costs to repair a bumper are $300 to $1,600, installed. The price of a bumper repair varies based on many factors, including the type of vehicle and the type of bumpe...Abstract: Base excision repair (BER) corrects forms of oxidative, …Jul 31, 2562 BE ... ... excision de base (ou BER pour Base excision repair en anglais) est l'un des mécanismes de réparation de l'ADN utilisé par les cellules ...FUdR-induced hypertonic stress resistance was partially dependent on sirtuins and base excision repair (BER) pathways, while FUdR-induced lifespan extension under hypertonic stress conditions requires DAF-16, BER, and sirtuin function. Combined, these results demonstrate that FUdR, through inhibition of TYMS-1, activates stress response ...The base excision repair pathway is an organism's primary defense against mutations induced by oxidative, alkylating, and other DNA-damaging agents. This pathway is initiated by DNA glycosylases that excise the damaged base by cleavage of the glycosidic bond between the base and the DNA sugar-phosph …An excision repair refers to the DNA repair mechanism that deals with the damaged …Apr 27, 2022 · Deoxyinosine is then converted into abasic sites by a DNA base excision repair (BER) glycosylase, N-methyl-purine DNA glycosylase11,12 (MPG). These abasic sites are cleaved by the BER endonuclease ... Base Removal. The first enzymatic step in BER is typically excision of a substrate base from duplex DNA by a DNA glycosylase, enzymes that catalyze the cleavage of the N-glycosidic bond between the substrate base and the 2’-deoxyribose creating an abasic site (8–11).There are several DNA glycosylases (Table 2), and all possess binding pockets …Base excision repair (BER) has evolved to preserve the integrity of DNA following cellular oxidative stress and in response to exogenous insults. The pathway is a coordinated, sequential process involving 30 proteins or more in which single strand breaks are generated as intermediates during the repair process. While deficiencies in BER ...Craniosynostosis repair is surgery to correct a problem that causes the bones of a child's skull to grow together (fuse) too early. Craniosynostosis repair is surgery to correct a ...Base excision repair is a process that removes and replaces damaged or misincorporated bases in one strand of the DNA that may generate mutations if left unrepaired. The damaged base is modified ...Base excision repair works by excising a single damaged base or nucleotide; this is under the mediation of DNA glycosylases cutting the bond between the nitrogenous base and the deoxyribose sugars. When the glycosylases remove the base, it creates an apurinic site if the removed base was a purine (adenine, guanine), or an …Mar 1, 2017 · A representation of the base excision repair (BER) pathway for removing oxidative damage. (A) Classical BER cycle initiated by a monofunctional glycosylase and (B) a BER cycle started by a bifunctional glycosylase. The orange “P” represents a phosphate, -OH represents a 3′-hydroxyl and a 5′-2-deoxyribose-5-phosphate is represented by dRP. The base excision repair (BER) pathway is a critical DNA repair mechanism for removal of damaged bases arising from oxidation, alkylation, or deamination (Krokan and Bjoras, 2013). BER is initiated by DNA glycosylases that excise the damaged base and completed by additional proteins that remove the remaining sugar–phosphate …Jun 20, 2007 · Base-excision repair has an important role in preventing mutations associated with a common product of oxidative damage to DNA, 8-oxoguanine. Recent structural studies have shown that 8-oxoguanine ... BER facilitates the repair of damaged DNA via two general pathways - short-patch and long-patch. The shortpatch BER pathway leads to a repair tract of a single nucleotide. Alternatively, the long-patch BER pathway produces a repair tract of at least two nucleotides. Base excision repair is a DNA repair mechanism that removes the chemically modified bases from the DNA. The Enzyme involved in Base excision repair is DNA gl...No matter how wonderful iPod technology is, there may come a time when your iPod freezes up and completely stops responding. No matter what corrupted the iPod, there is a way to re...Apr 20, 2547 BE ... The DNA Repair Interest Group is concerned with all forms of DNA damage and repair. As a major defense against environmental damage to cells DNA ....