Talk:Homologous recombination/GA1

GA Review
The edit link for this section can be used to add comments to the review.''

Note: I try to be as thorough as possible with my GA reviews, bordering on FAC in some areas.

The article is in an excellent condition. So as to not waste your time, and considering your plan to take this to FAC, I shall do my utmost to point out the trivial errors that those at FAC (including me...) would otherwise uncover. Fortunately, I'm not nearly as intimidating.

Important comment: As part of the FAC process, the issue of Alternative text for partially sighted readers using a screenreader, will arise and it would be best to prepare it as part of the GA review. It's quite daunting providing it for technical articles, but do read the section on chemistry for help and ask me.
 * I've made a first attempt at alt text for each image in the article. I don't think the alt text for the image for the RecBCD pathway in 'In bacteria' or the image for the DSBR/SDSA pathway in 'In eukaryotes' is up to par.  However, if I were to include even abbreviated descriptions of the images, it seems like they inevitably would be much longer than the 'Better alt text' for the chemistry example in WP:ALT.  Any suggestions would be appreciated. Emw2012 (talk) 16:32, 10 September 2009 (UTC)
 * My suggestion for the second image is to perhaps entirely omit text and simply put "See adjacent text", that is if the adjacent text is essentially just being illustrated by the diagram. Otherwise something like "See caption" would be more appropriate. This may be the same for the third image, but my understanding is not sufficient to suggest whether it is or not.
 * *The last image: would the caption be better as "A chimeric mouse, whose genes were targeted for the agouti coat color gene, with its offspring"? MasterOfHisOwnDomain (talk)
 * In my opinion, not quite: "whose genes were targeted" seems inaccurate. Perhaps this would work: "As a developing embryo, this chimeric mouse had the agouti coat color gene introduced into its DNA via gene targeting.  Its offspring are homozygous for the agouti gene." Emw2012 (talk) 19:44, 12 September 2009 (UTC)
 * Fine, it sounds currently as if the mouse is a gene, which even with my basic understanding doesn't seem correctly communicated. MasterOfHisOwnDomain (talk)
 * So changed. Emw2012 (talk) 21:45, 12 September 2009 (UTC)

Lead

 * Genetic material could be linked to "Gene" surely?
 * I'm concerned that linking 'genetic material' to 'gene' would suggest that only genes are involved in the exchange. Because the main requirement is that HR involve DNA of similar or identical sequence, much of the genetic material exchanged need not actually be genes. Emw2012 (talk) 19:13, 3 September 2009 (UTC)
 * In that case would some examples be possible? MasterOfHisOwnDomain (talk)
 * Would the descriptions of the various mechanisms in bacteria and eukaryotes not suffice as examples? If the phrase 'genetic material' is indeed confusing along the lines you mention, I could change it to 'nucleotide sequences'.  Although that phrase seems slightly less reader-friendly than 'genetic material', I think it would prevent confusion better. Emw2012 (talk) 13:35, 13 September 2009 (UTC)
 * I think so too. Much of the rest of the article becomes less friendly to a casual reader, so I don't see an issue with changing this to something more accurate. MasterOfHisOwnDomain (talk)
 * Done. Emw2012 (talk) 15:44, 13 September 2009 (UTC)


 * "physical breaking and rejoining of DNA" is there no scientific name for these processes (that could be linked)?
 * Here, "physical breaking" can refer to either unintentional or intentional DNA breaking (e.g., from ionizing radiation or topoisomerases, respectively). "Physical breaking" is even more general in that it can also be taken to mean breaking of single-stranded DNA (as in cutting back DNA in the resection phase of HR) or double-strand DNA (as done by IR or topoisomerases).  So I can't see right now how I could link to something that would convey such information.  "Rejoining of DNA" seems easy enough to take care of. Emw2012 (talk) 19:13, 3 September 2009 (UTC)
 * Fair enough.


 * "Although most widely used in cells to accurately repair double-strand breaks in DNA": does this mean: in cells, the process is most widely used to..., or: the process is most widely used in cells. If it's the former consider:
 * "Although most widely used to accurately repair double-strand breaks in the DNA of cells..."
 * I mean the former, but the use of "cells" in your suggestion shows how the word is extraneous. If not in cells, where would this DNA-centric process be used?  In the extracellular matrix?  Certainly not.  It seems like it would be intuitive to the reader, even if they didn't have much of a background in biology, that this process occurs in cells. Emw2012 (talk) 19:13, 3 September 2009 (UTC)
 * Okay, not entirely sure what extracellular matrices are, but the slight confusion of meaning has been resolved nonetheless!


 * If it's the latter consider replacing the "used in" with "used by [cells]".
 * The wikilink of "conserved" is "Conservation (genetics)", but it takes the reader to a disambiguation page.
 * Fixed Emw2012 (talk) 19:13, 3 September 2009 (UTC)


 * "eukaryotic" requires linking, and I would consider the first occurence of it after the lead ("eukaryotic genomes" in "In bacteria") to require it also; I had a discussion with another user over whether or not terms appearing in the lead and then subsequent chapters should be linked twice. I would like to hear opinion on the issue.
 * Fixed. (I think linking once per section can be helpful in many cases.) Emw2012 (talk) 19:13, 3 September 2009 (UTC)
 * Okay. Well as per your response and the fact that this is already the case for some other technical terms (Holliday junction), I have gone ahead and wikilinked some terms linked in the lead but repeated in the text.


 * "Since their dysfunction" what dysfunction is this?
 * In this case, "their" is a placeholder for "the proteins that facilitate homologous recombination", mentioned in the subsequent clause. Emw2012 (talk) 19:13, 3 September 2009 (UTC)
 * Sorry I phrased that poorly. My issue was: "What actually is the dysfunction?" I thought it might refer to the following, but I don't actually know that the dysfunction is. MasterOfHisOwnDomain (talk) 19:31, 3 September 2009 (UTC)
 * I'm not exactly sure what the actual dysfunction is, just that the proteins are 'dysfunctioning', 'not working', etc. In many cases I think this ignorance of precisely what has gone wrong extends to the scientific community.  That is, while (as I understand it) HR proteins can be broadly categorized as 'functional' or 'dysfunctional', many times the mechanisms of many of said proteins are poorly understood among researchers.  Maybe the actual mechanics behind dysfunction are discussed for some proteins; I'll look into this.  Emw2012 (talk) 16:04, 4 September 2009 (UTC)


 * Okay I shall leave this comment unstruck for the moment. MasterOfHisOwnDomain (talk)
 * Looking back at that sentence, I see the nature of dysfunction is described in at least some detail in the 'Effects of dysfunction' section. As discussed in that section, dysfunctions in HR proteins are caused by mutations in their associated genes, which cause rates of HR to either decrease (as with dysfunctional BLM protein) or increase (as with dysfunctional BRCA1).  If you think this level of detail is appropriate for the lead, could you suggest how to incorporate it while preserving summary style? Emw2012 (talk) 17:21, 12 September 2009 (UTC)
 * That is quite a tricky one. As you say, the summary style of the lead must be preserved, but equally a term cannot be left completely undiscussed. I'll give it a bit more thought in my little free time. MasterOfHisOwnDomain (talk)


 * "Adapt" links to a disambiguation page. MasterOfHisOwnDomain (talk)
 * Fixed. Emw2012 (talk) 13:35, 13 September 2009 (UTC)

In bacteria

 * "Understanding of homologous recombination is most advanced for" could be condensed to "Homologous recombination is best understood for"
 * Done. Emw2012 (talk) 19:28, 3 September 2009 (UTC)


 * "pathway" is unclear, please explain briefly or wikilink
 * Done. Emw2012 (talk) 19:28, 3 September 2009 (UTC)


 * "complexes" same as above
 * Changed "complex" to "bind", let me know if further explanation would be good. Emw2012 (talk) 19:28, 3 September 2009 (UTC)


 * I would expect the paragraph starting with "The invading 3' overhang causes one..." to have at least one in-line citation, same for the last paragraph of that sub section
 * Done. Emw2012 (talk) 05:14, 9 September 2009 (UTC)


 * "There are two types of products resulting from recombination" possibly condensed to "Two product types result from recombination"
 * Done, though I opted for "two types of products...". Emw2012 (talk) 05:14, 9 September 2009 (UTC)


 * RecF Pathway: "Bacteria use the RecF pathway of homologous recombination, also called the RecFOR pathway, primarily to repair single-strand breaks in DNA; the pathway can also substitute for the RecBCD pathway in repairing DNA double-strand breaks." my suggested condensed version, which makes space for my next issue:
 * "the pathway can also substitute for the RecBCD pathway in repairing DNA double-strand breaks" under what circumstances? If this is covered by the next statement (of being less understood) then that needs to be made clear (e.g. the reason for this is unknown). MasterOfHisOwnDomain (talk) 18:09, 3 September 2009 (UTC)
 * Done. Emw2012 (talk) 17:21, 12 September 2009 (UTC)

I don't have time to address your last several concerns until Tuesday. At that point I'll finish polishing the 'In bacteria' section and move on to any other suggestions you make in the meantime. Thanks for your review thus far! Emw2012 (talk) 19:28, 3 September 2009 (UTC)
 * Okay, I'll make further comments in the meantime and then put the article "On hold" once you return on Tuesday. MasterOfHisOwnDomain (talk) 19:38, 3 September 2009 (UTC)


 * "When these new phage virions infect other bacteria"; phage virions isn't a term I can find. "Bacteriophage" seems to be the accepted term for what I believe you are talking about. MasterOfHisOwnDomain (talk) 11:34, 24 September 2009 (UTC)
 * 'Phage' is a common synonym for 'bacteriophage' -- note its use even in the lead of the article on bacteriophage. 'Virion' is the word used to describe a single, fully functional virus particle outside its host cell. Emw2012 (talk) 16:35, 24 September 2009 (UTC)  On second thought, although 'phage virions' is technically correct, 'bacteriophages' is just as correct and more reader-friendly.  So changed. Emw2012 (talk) 16:45, 24 September 2009 (UTC)

In eukaryotes
I've made a lot of rewordings in the intermittent sections, please revert and discuss if the meaning of any sentences have been changed.


 * "When left unrepaired" would there be an issue with "left broken"?
 * In that sentence "broken" and "breaks" appear too close together -- I changed this phrase to simply "Left unrepaired". Emw2012 (talk) 05:14, 9 September 2009 (UTC)


 * "large-scale chromosomal rearrangements" personally sounds better as "large-scale rearrangement of chromosomes" MasterOfHisOwnDomain (talk) 12:40, 4 September 2009 (UTC)
 * Done. Emw2012 (talk) 05:14, 9 September 2009 (UTC)

Evolutionary origins

 * "DMC1" is capitalised in one instance. I'm assuming it's just a formatting error, but since it could be something else and you would probably rather edit your own article, I shall leave it for you. MasterOfHisOwnDomain (talk) 20:41, 23 September 2009 (UTC)
 * That instance of DMC1 is capitalized because it refers to the gene; Dmc1 refers to the protein. The nomenclature is sometimes tricky to track, but it's the convention in molecular biology. Emw2012 (talk) 02:57, 24 September 2009 (UTC)
 * Okay, and I presume a user knowledgeable in molecular biology would know this? I have no issues with it then, however I can see casual users (i.e. such as me, who believe it might be a formatting slip) trying to alter it. Would a note explaining the naming conventions be appropriate? MasterOfHisOwnDomain (talk) 11:18, 24 September 2009 (UTC)
 * I think gene nomenclature is an inconsistently defined and worse understood topic, even among people with a background in molecular biology. I can't think of an appropriate way to include a note about gene nomenclature in the text; any attempt I think of seems like it would be unnecessarily distracting.  If you can think of something, feel free to add it.  I think any good-faith changes to the capitalization could be fixed by a politely worded reversion with a pointer to the page on gene nomenclature. Emw2012 (talk) 16:30, 24 September 2009 (UTC)
 * Actually, on second thoughts, you could include a comment only visible while editing. That way a good faith editor would be made aware upon trying to change things. MasterOfHisOwnDomain (talk) 19:02, 24 September 2009 (UTC)
 * The note will require some understanding of the subject, so you should take a look at this: Manual_of_Style. MasterOfHisOwnDomain (talk)
 * Good point, done. Emw2012 (talk) 19:07, 24 September 2009 (UTC)

Technological applications

 * "The human body is of particular interest." with regards to the previous sentence? If so consider a semi-colon or abridging the sentences better.
 * Sentence removed. Emw2012 (talk) 20:16, 12 September 2009 (UTC)


 * "This work yielded Mario Capecchi, Martin Evans and Oliver Smithies the 2007 Nobel Prize for Physiology or Medicine." Couple of issues:
 * *yielded and any synonym thereof (e.g. produced) seems slightly odd for this sentence.
 * What is "this work"? Is it all of the aforementioned? It should be, if known and applicable, the exact criteria for their award (i.e. for work into the use of homologous…). MasterOfHisOwnDomain (talk) 19:33, 12 September 2009 (UTC)
 * I've tried rewording the verbatim criteria noted here to indicate the role homologous recombination played in the award. Emw2012 (talk) 20:16, 12 September 2009 (UTC)
 * "Methods like SCHEMA", needs elaborating; is it an acronym? MasterOfHisOwnDomain (talk)
 * I just created a stub for SCHEMA and wikilinked it. It's apparently not an acronym. Emw2012 (talk) 01:20, 19 September 2009 (UTC)
 * Okay that's great. MasterOfHisOwnDomain (talk) 12:33, 20 September 2009 (UTC)
 * "isoprenoid biosynthesis" needs wikilinking, either separately per term or together (hence why I'll leave it to you who knows best!). MasterOfHisOwnDomain (talk) 18:02, 21 September 2009 (UTC)
 * Done. Emw2012 (talk) 02:04, 22 September 2009 (UTC)


 * The article talks of chimera proteins and then skims over them as "chimeras" ("the chimeras produced by …"). Are chimeras and chimera proteins the same, and might it be appropriate to note this (in brackets)? MasterOfHisOwnDomain (talk) 21:41, 25 September 2009 (UTC)

Final comment
I am unable to find any further issues with the article at the moment, though this will undoubtedly showcase my faults in reviewing (I'm sure the FAC process will be able to dig up more points. The article is in a great shape though and should pass without much fuss (though as I've noted, I can't guarantee anything). However it would be unfair to delay it any longer in passing through GA. Please fix the issue with chimera proteins as listed above before taking it to FAC.


 * Result of review: Pass
 * MasterOfHisOwnDomain (talk) 14:23, 29 September 2009 (UTC)