Wikipedia:Reference desk/Archives/Science/2009 March 1

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March 1

Lineage dna testing

I've been thinking about getting some DNA testing done to learn a little bit more about my family's past. What are some of the most reputable companies. I'm on a budget, so I don't want to be spending my payckeck to get this done either. --Ghostexorcist (talk) 17:39, 1 March 2009 (UTC)

What kind of testing do you mean, particularly? I mean, are you looking to see, say, if you and your siblings come from the same biological parents (for example), or are you looking for, say, one of those "how many racial groups am I made of" sort of tests (which are extremely problematic, it must be said), or, are you looking to compare some old lock of hair found with other DNA, or what? I imagine all of these would require somewhat different labwork, probably are done by different companies. --98.217.14.211 (talk) 18:02, 1 March 2009 (UTC)

(ec - I'm assuming the 2nd of the anon's options) You'll probably learn more by tracing your family free the old fashioned way - go through censuses, birth, marriage and death certificates as the local records office (and other records offices wherever your family have lived), baptism records at churches, etc., etc.. There are people (and websites) that can help you with such things. DNA testing will only give you very vague information, if anything. --Tango (talk) 18:05, 1 March 2009 (UTC)

We would be able to tell you more if you were more specific about exactly what you want to accomplish by DNA testing. One of the best known companies is Family Tree DNA [1], which has a large associated database due to its (comparatively long, for a DNA company) history. It performs Y-DNA and mtDNA testing. Another more recent entry is 23andme, [2] which tests autosomal markers as well as Y-DNA snps and mtDNA, though less extensively than FTDNA. There are other comments which I would make about companies to avoid that are more suited for a less public forum; feel free to e-mail me at the "E-mail this user" link on my talk page -Nunh-huh 18:09, 1 March 2009 (UTC)

You also may be interested in the International Society of Genetic Genealogy (ISOGG) y-DNA testing comparison chart. the ISOGG mtDNA testing comparison chart, and other information at the ISOGG site. - Nunh-huh 18:15, 1 March 2009 (UTC)

If you are thinking about these "what races am I made of" tests, you should really be aware that the methodology is very problematic and the information they give you (in terms of the % black, % white, etc.) is often scientifically quite meaningless. --98.217.14.211 (talk) 19:20, 1 March 2009 (UTC)

Unless you have a specific question (e.g. which allele do I have at a specific locus), you would be better off putting the money you intend to spend on this in a high interest savings account for 5-15 years. In that time, both sequencing technology and our knowledge of DNA sequence variation will have advanced significantly, so you can get a lot more bang for your buck. Currently, genome sequencing is expensive and the genealogy information they can provide is limited to say the least. Rockpocket 19:34, 1 March 2009 (UTC)

Well, yes and no. Some considerations include the likelihood that the person you want to test will die before the test reaches your desired price; one alternative to testing now is DNA storage. - Nunh-huh 19:59, 1 March 2009 (UTC)

Fair point. But even if time is an issue (unless you have some particularly unusual or rare genetic features or know nothing about your biological family) you would likely infer, with similar confidence, as much about your ancestry with a little old fashioned genealogy as you would from any commercially available DNA testing. DNA storage is a good idea, though. I have mine cryopreserved in a number of places (I used to use it as a control for various DNA testing I used to do!). Rockpocket 21:21, 1 March 2009 (UTC)

Like I previously stated, I want to learn a little more about my family's past, so it would be one of those "how many racial groups am I made of". --Ghostexorcist (talk) 02:04, 2 March 2009 (UTC)

Tests that come back with results like "70% European, 20% East Asian, 10% African" are really more or less a waste of money. (See our Genealogical_DNA_test#Geographic_origin_tests ). They're inadequately validated and provide very little information for the money provided. Have a look at what 23andme is offering: they test your genotype via a DNA chip rather than by sequencing. The ethnicity portions of the test don't claim to provide more information than they actually do, and in addition to the ethnicity portion you are likely to find interesting genetic information. - Nunh-huh 05:48, 2 March 2009 (UTC)

voice on the moon

I have reed that when Neil Armstrong go to Cairo ,where he herd a voice of Azan (Muslim calling before prayer) ,he mentioned that I have herd this voice on moon.I think this event is not happened.But I want to know your opinion —Preceding unsigned comment added by True path finder (talk • contribs) 19:41, 1 March 2009 (UTC)

Later, Muslims were elated with the baseless rumour that Neil Armstrong had converted to Islam as he had heard the call to prayer (azan) on the moon. Another version attributed his conversion to his having seen signs of the ‘parting of the moon’ as believed by Muslims. [3] This rumour is also revealed as untrue in numerous biographies of Armstrong, e.g. [4] and books about Islam, e.g. [5] Rockpocket 19:48, 1 March 2009 (UTC)

I'm sure he didn't say that (of if he did - then I'm certain it was a remark made out of courtesy that was misinterpreted)...and Rockpocket's references confirm that. But in any case - there is no air on the moon. There is no sound there. If he had truly heard something it would have had to come over his radio - and that could just as easily have come from earth as from the moon. He would certainly know this! Hence, he would have known that he either imagined the whole thing - or heard some sound from mission control. It's really an impossible story. SteveBaker (talk) 23:18, 1 March 2009 (UTC)

Shows what you know! God is everywhere, which obviously includes Neil Armstrong's inner ear. --Sean 15:32, 2 March 2009 (UTC)

I don't know about that - but the Azan is a very human human standing at the top of a tower yelling REALLY loud. I don't think god or gods are very much involved in that bit. SteveBaker (talk) 20:12, 2 March 2009 (UTC)

Every place I have ever been has always used a loudspeaker with electronic amplification to replace the "really loud yelling". Most of them used pre-recorded versions, typically MP3 recordings of famous Azans such as those of Haram Ash-Sharif, or famous poetic recitations recorded in the 1950s and 1970s. I've also seen phonograph records and audio-cassettes used in places where iBooks don't penetrate the market so thoroughly. I would hope that this demonstrates that the majority of mainstream Muslims can adapt and adopt science and technology to the culture, without spewing out mindless fringe pseudo-scientifico-theologicial nonsense. Nimur (talk) 21:43, 2 March 2009 (UTC)

Presumably on the Moon the 'loudspeaker' would be arranged so that the sound is conducted through the ground. —Tamfang (talk) 03:06, 3 March 2009 (UTC)

I believe that at least one pair of moon-walkers tried that experiment. Turning off their radios and yelling really loud to see if the other person could hear them from a foot or two away...without luck apparently. SteveBaker (talk) 00:15, 4 March 2009 (UTC)

Did they try it with helmets touching? That ought to work reasonably well. --Tango (talk) 00:25, 4 March 2009 (UTC)

Do Homophobic Men Harbor Secret Homosexual Desires?

Do they? Or is it just a strategy of the gay community to strike back?--83.59.239.32 (talk) 19:51, 1 March 2009 (UTC)

Some probably do, I very much doubt all do. I doubt there are any real studies on the subject - I'm not sure homosexual homophobes would describe themselves as such on a questionnaire (even an anonymous one). Am I the only one that hates the word "homophobe"? The word should mean "one who is afraid of things that are the same". --Tango (talk) 19:55, 1 March 2009 (UTC)

And pontiffs should build bridges. LANTZY^TALK 04:49, 2 March 2009 (UTC)

It is better to pontificate than to curse the river! —Tamfang (talk) 03:02, 3 March 2009 (UTC)

Of course, we have an article (well, a section): Homophobia#Internalized homophobia. --Tango (talk) 19:57, 1 March 2009 (UTC)

I would kinda think this belongs at a culture/sociology desk... but I don't know if we have one. You could make a good case for projection out of many incidences of fanatical hatred. But that's gay-bashing rather than homophobia - IMO, two very different critters. I don't really care who does or doesn't like my sexuality, as long as they leave me alone about it.

(Nonetheless, $20 says Fred Phelps is gayer than a mauve flamingo in buttless chaps.) arimareiji (talk) 20:13, 1 March 2009 (UTC)

I guess they would come under the Humanities desk. There is always a lot of overlap between the desks, though. --Tango (talk) 20:29, 1 March 2009 (UTC)

Reaction formation also touches on the subject. But I doubt ALL homophobic men are actually gay. Then again, some say that most people aren't 100% homosexual or 100% heterosexual. --Bennybp (talk) 20:38, 1 March 2009 (UTC)

Some men certainly do: just take a look at Ted Haggard, whose anti-gay rhetoric got a delicious end when the male prostitute he'd been banging for three years outed him. (Generally speaking, I'm not a big fan of outing people, but Haggard certainly had it coming.) Or Senator Larry Craig, whose legislative career was far from gay-friendly, but who still felt the urge to cruise airport bathroom stalls for a little man-on-man action. There are plenty of other examples. But does that mean that all homophobes are closeted homosexuals? Of course not. You don't need to have complex psychological self-image issues for that. You can just be an asshole. -- Captain Disdain (talk) 20:39, 1 March 2009 (UTC)

I nominate the last two sentences for Comment of the Day. Thanks for the laugh. ^_^ arimareiji (talk) 21:51, 1 March 2009 (UTC)

In there interests of WP:BLP, we should note that Larry Craig does not self identify as homosexual and he says that the bathroom stall incident(s) were misunderstandings. [6] Rockpocket 00:13, 3 March 2009 (UTC)

Also, Ted Haggard only shared unspecified "sexual immorality", with the admission only of massages, with his motel-mate. So there's hope for these heterosexuals yet! --Sean 02:04, 3 March 2009 (UTC)

Why do all these homosexuals keep sucking his cock? LANTZY^TALK 05:42, 3 March 2009 (UTC)

That was definitely the Link of the Week. XD And could be a great Kids in the Hall skit. arimareiji (talk) 05:58, 3 March 2009 (UTC)

Pfft. WP:BLP doesn't apply; this is not a biography, this is a conversation, and obviously my personal opinion. In fact, I'll grant you that it's possible that Craig, an unmarried man, is completely heterosexual, and this is all just a big misunderstanding, just like it was when it was rumored that he was involved in the sex scandal that involved congressional male pages, back in the 80s. And perhaps he was indeed just in the bathroom minding his own business, when a terrible misunderstanding occurred. And all those other allegations may be nothing but lies. It's possible. -- Captain Disdain (talk) 07:01, 3 March 2009 (UTC)

How long would my body take to realize I'm healthy again?

I'm sneezing, my muscles are aching, I'm coughing and it tastes of blood. Suddenly an alien from outer space appears in my bedroom, pointing its mobile at me. It does a quick scan, then presses a button. A little flash of light, and all DNA and RNA of any microbes, is teleported away. The alien, too, vanishes.

Given the above scenario would be true, how long would my immune system take to realize there's nothing more to do than to bail out the now defunct cells (or hulls, if viruses) of the invaders and go back from war to healthy, watchful sentry? Would that be minutes, seconds, hours or days?

Same question the other way round: say that alien bastard appears again, putting everything back in place, muttering something about misspelled names and how we earthlings all look alike, how long would it take to start the immune reaction up again? 93.132.153.222 (talk) 20:14, 1 March 2009 (UTC)

Getting rid of all microbes would be a bad idea - you would get terrible stomach cramps, at the very least (maybe worse). There are lots of bacteria in the gut that are very important. If you revise your question to just disease causing microbes, then I don't know! --Tango (talk) 20:36, 1 March 2009 (UTC)

I'm not a ruminant feeding on grass, why should I get stomach cramps? 93.132.153.222 (talk) 20:55, 1 March 2009 (UTC)

Although you're not a cow, what Tango said is still true. Check out Human flora. Also, I think it's debatable whether or not you would still call yourself "healthy" if your body doesn't "recognize" that you are. There's lots of shit that your body can do to you to make you feel like shit without the help of microbes, like autoimmune disorders, degenerative muscle diseases, and endocrine issues (like diabetes). If you feel like shit, you're still not "healthy."--Shaggorama (talk) 21:06, 1 March 2009 (UTC)

I wrote realize, not recognize. I'm not a native speaker and may have a false concept about some words, if so, please correct me. The human flora article doesn't really tell me why I should get stomach cramps. The normal flora can act as opportunistic pathogens, cause acne, dissolve tooth enamel and assist global warming by producing methane. On the pro, it prevents the really bad microbes from growing, produce some vitamins and help digest some of the complex sugars. (In case I'd have lactose intolerance that would really give me stomach cramps, I know people who have.) 93.132.153.222 (talk) 21:49, 1 March 2009 (UTC)

I think, in this context, 'realise' and 'recognise' mean the same thing. As you say, one of the things the bacteria in your gut do is aid digestion - without them, you can't digest food properly and that gives you stomach cramps. It's a fairly common side effect of taking lots of antibiotics. --Tango (talk) 21:55, 1 March 2009 (UTC)

Thank you for the realise/recognise help. As for the food digestion, I think this is only a problem when other bacteria digest what the good ones would, but to different end products. If there are no (no, none at all) bacteria around that would not happen. Otherwise stomach cramps from taking antibiotics would be quite common. In the above scenario there wouldn't even be yeasts to do a maldigestion. 93.132.153.222 (talk) 22:10, 1 March 2009 (UTC)

Actually, I've had stomach trouble most of the times I've taken antibiotics... but I see what you mean. No cramps from gas, but it might still cause trouble from osmotic issues. arimareiji (talk) 22:30, 1 March 2009 (UTC)

I'm not sure about the removal of DNA/RNA from microbes, but a complete lack of exposure to "germs" in general can act to weaken the immune system (and usually at a bad time)! For example, if you were subject to using hospital pillows for a number of days, your immune system may be weakened to the pillow fungi in ordinary pillows. ~AH1^(TCU) 00:26, 2 March 2009 (UTC)

In an attempt to answer the question... The amount of time it took to get your body back to healthy would vary from symptom to symptom and person to person. A rough analog might be found in the case of allergies, where the ingestion of antihistamines can get you back on your feet in anything from a few minutes to a few hours, depending on how inflamed your tissues are, etc. The allergen doesn't actually do any damage (almost by definition), so the issue is just about calming your system down and then letting your body get back to normal. In a similar vein, a persistent symptom can keep going indefinitely even after the disease is finished. On a couple of occasions I've gotten over a cold, but been unable to shake a cough that the doctors said was simply due to the irritation of coughing... which made me cough - and onwards into a vicious cycle. The alien could have cured me an an instant, but I would have kept coughing regardless. Your second question probably relies most heavily on the incubation time of the particular bug. Matt Deres (talk) 17:51, 3 March 2009 (UTC)

Psychology: why is working on computer dull, but computer games fun?

Doing administrative work of some kind using a computer may require the same amount of decision making, intellect, and time, as playing a computer game. But one is dull, the other fun. What are the differences between the two that make it either fun or work? NB:- this is not a homework question. I'm wondering how I can make my own work more interesting, and motivate myself to do more of it more avidly. Thanks. 89.241.154.51 (talk) 21:59, 1 March 2009 (UTC)

I don't think the computer part is relevant - work is (or can be) dull, games are fun, regardless of the medium. I'm not sure there is much you can do to make work interesting - either you're doing work you find interesting, or you aren't. You could try getting a different job. I think the key difference is that you choose what games to play, so you choose games that you find interesting. You generally have less choice about what work you do. --Tango (talk) 22:06, 1 March 2009 (UTC)

I think it's the liberty to do it or leave it. If you would be forced to play computer games (say you have a payed job as tester that your income depends on) there would be no fun in it. 93.132.153.222 (talk) 22:14, 1 March 2009 (UTC)

Some people could call it the perfect combination of skill level + job + fun. Julia Rossi (talk) 22:29, 1 March 2009 (UTC)

Annoyingly, a lot of people think that - and it's a myth that's fed by the colleges that offer courses in game technology. In truth it's boring, repetitive, exacting work. They don't just play the finished game for a week or two - they play the exact same game over and over for YEARS. To start with the game is utterly bug-ridden - it'll crash at the most annoying moments. You'll get halfway through some interesting new part - and find that the rest of the 'quest' or whatever hasn't been written yet. They have to push it in every way - go everywhere in the game levels - try to do things as stupidly as possible as well as with the most skill possible. And they have to log what goes wrong (and in the early days, LOTS of things go wrong) - there are daily reports to be made. They find a bug and report it - then every day from then until it's fixed, they have to try the same complicated thing and report on whether the latest code release from the programming/art/level/audio teams fixed it. Even after it's fixed - they have to recheck it periodically to ensure that it didn't 'come back' later. Trust me - it's about as far from playing an enjoyable game as you can imagine. Job prospects as a game tester are pretty limited - there is a team leader job to aspire to - but there aren't lots of grades of play tester that you can progress through. It's also pretty low paid because of the supply-and-demand thing. So many kids think (as you evidently do) that this would be the most fun thing in the world - that the supply of willing workers is high - so the pay is low. Trust me - this is NOT a great job. SteveBaker (talk) 23:05, 1 March 2009 (UTC)

Yet, for some reason, people still recommend game testing as a good way to get into the games industry on your way to becoming a developer. I've never understood where people get that idea... --Tango (talk) 23:34, 1 March 2009 (UTC)

Not really - I mean, it's possible I suppose - but I don't see hoards of people who came at it that way. There are no skills you learn as a play tester that are of much use through the rest of the development chain. I suspect that those who do make it are taking community college classes in something relevent. The best way in is to take a proper college course. Someplace like Full Sail University in Florida which seems to provide a lot of the talent that feeds into the business. Alternatively, a solid, proven background in 3D art, programming or the technical side of music/audio recording. I had been a 3D graphics programmer for a gazillion years before I got into the biz. SteveBaker (talk) 00:38, 2 March 2009 (UTC)

I'm a game developer - we have people within our team who's job it is to play games all day - they are in our quality assurance group. I think pretty much everyone agrees that it's the least exciting job in the company. The reason is because when you play a game for the first time, it's new - it's different - and game designers work hard to keep the experience changing from start to finish by adjusting the play difficulty upwards as you progress through the levels - and making the levels fairly diverse - adding new abilities for your avatar to use - then (perhaps) horribly limiting them to make a new challenge. That simply doesn't happen with administrative work, spreadsheets, word processors - what you have on the first day you use WORD you have on the last day. Our play-testers get just as bored as you do because they play the same game over and over - literally thousands of times each over periods of one to two years. It's a job...it's not "fun" most of the time. But you'll only play our games a few times...you won't (hopefully!) get bored with it before the next game comes along.

Having said that - I don't entirely agree with your premise. Not all non-game-things one does at a computer are boring and repetitive. My specialty is programming - and I LOVE to program. When the difficulty of what I'm doing at work isn't challenging enough, I spend my off hours writing OpenSource software...sometimes my own games..just to keep my skills sharp. I love working at the computer.

SteveBaker (talk) 22:55, 1 March 2009 (UTC)

What you need is, as Steve makes clear, a job that does for you what the games do: gives you interesting, changing problems. There are many jobs that can do that. If you aren't in one, figure out what you need to do to get into one. Life's too short to do incredibly dull, repetitive work all day long. --98.217.14.211 (talk) 01:36, 2 March 2009 (UTC)

Unfortunately, for 90% of the people, life becomes shorter when you choose not to do dull, repetitive work all day. In an ideal world, everyone would be able to support themselves with jobs that meet their skill set and interests. In the real world, people often take whatever job they can get in order to survive. Sometimes, if they don't like it, they can find another job they don't like just as much as the last one. And then they can either stick with that job they don't like, or find yet another unfulfilling job. Either that, or live on the street and panhandle. --Jayron32.talk.contribs 02:41, 2 March 2009 (UTC)

Obviously we don't live an ideal world—certainly not at the moment—but the idea that people get into their heads that their only two options are shitty job they don't like or panhandling is usually quite false. From what I can tell most people end up becoming quite fatalistic quite quickly. There are some people who are in exceptionally bad circumstances and are lucky to get whatever they can find. But there are quite a lot of people in a more middling category. I don't deny though that making radical changes means making radical choices—one has to figure out one's priorities, because not all situations are mutually reinforcing. --140.247.253.176 (talk) 19:36, 2 March 2009 (UTC)

I want to fly over the program to spot anything awry. Neaaaagh I push my joystick forward and dive down to see what's happening. It's a horrid great big bug. I press the button and dat dat dat I've blasted it. It dies with a shriek and explodes. I splat a sticker on the side of my cockpit with the others. Yeah another one bites the dust. There, you jus need the right atttude to software. Dmcq (talk) 01:04, 2 March 2009 (UTC)

Zackly. An that's just the spreadsheet! :)) Julia Rossi (talk) 01:34, 2 March 2009 (UTC)

There you go! Like increasing numbers of games companies, we use the SCRUM development method - and the morning scrum meetings (when things are going well) has a lot of that feel to it. Lots of energy - lots of good feelings about nailing problems. When you nail a bug that's been annoying everyone or show off a new feature - expect applause...cheers...tons of energy. On Friday - late afternoon, we all show off our latest stuff, the company pays for beer, food - we play RockBand...etc. It's not a 'normal' job - work hard, play hard, be a real team - never leave a buddy behind...that kind of thing. SteveBaker (talk) 02:39, 2 March 2009 (UTC)

Looks good. I like in particular the work had not long bit. I've always wanted to work into the rules that it is the teams that get the job done without fuss and in time get extra resources and are kept together and used as a group to fix problems rather than being split up and used as resources where things are failing. Too often it is the person who is late and then works hard fixing a mess that gets the praise and promotion. A moderate amount is fine but more should be given for doing it without going into headless chicken mode. Dmcq (talk) 09:03, 2 March 2009 (UTC)

Seems like games testing is not much different then testing any other software, except games are at least fun the first couple of weeks. 65.167.146.130 (talk) 16:27, 2 March 2009 (UTC)

Playing a game constantly for two weeks in which only half a level is written and even that doesn't work properly doesn't sound like much fun to me... --Tango (talk) 17:43, 2 March 2009 (UTC)

Yes, exactly. On week 1: The 'world' is four large white cubes sitting on a checkerboard. Your character is borrowed from the last game you wrote - you can walk and run but not jump, climb or crawl and none of the weapons are implemented yet...the first 'enemy' or 'puzzle' is about six months away. Enjoy! (Actually, we usually don't start using play-testers in any great numbers until we're further along than that - but at worst, it can be that bad.) SteveBaker (talk) 20:09, 2 March 2009 (UTC)

Responding to the title question rather than to the discussion: You need to consult that great scientist Mark Twain, who wrote up the definitive answer to this quandary in one of his paradigm-changing papers, entitled The Adventures of Tom Sawyer. --Trovatore (talk) 20:11, 2 March 2009 (UTC)