doktorit\u00f6\u00f6<\/a> raames loodud y-mer meetod l\u00e4heneb sellele probleemile teisiti. Selle asemel, et otsida \u00fcksikuid muutusi DNA-s, anal\u00fc\u00fcsib see kogu Y-kromosoomi ulatuses l\u00fchikeste DNA-j\u00e4rjestuste mustreid. Nii piisab haplogrupi m\u00e4\u00e4ramiseks v\u00e4ga v\u00e4ikesest andmemahust: v\u00e4hem kui 0,01-kordsest genoomi katvusest. See t\u00e4hendab, et arheogeneetikud saaksid t\u00f6\u00f6tada senisest k\u00fcmneid kuni sadu kordi v\u00e4iksemate andmetega.<\/p>\nMeetod kasutab seni v\u00e4hekasutatud DNA-d<\/p>\n
Meetodi idee tekkis k\u00fcsimusest, kuidas m\u00e4\u00e4rata isaliini sugulust v\u00e4ga vanade matmispaikade s\u00e4ilmete vahel. Selle p\u00fcstitas Tartu \u00dclikooli populatsioonigeneetika kaasprofessor Toomas Kivisild.<\/p>\n
Vana DNA puhul ei t\u00f6\u00f6ta sageli h\u00e4sti tavap\u00e4rane PCR-meetod, mis vajab tervemat DNA-d. Kuigi Y-kromosoom moodustab umbes \u00fche protsendi kogu DNA-st, ei ole seni kasutatud umbes poolt sellest ehk nn heterokromatiini. See sisaldab korduvaid DNA-j\u00e4rjestusi, mida peeti varem v\u00e4heoluliseks.<\/p>\n
Tarmo Puurand m\u00e4rkas aga just neis nii-\u00f6elda r\u00e4mps-DNAks peetud piirkondades mustreid, mida saab tuvastada ka v\u00e4ga v\u00e4ikese DNA hulga korral.<\/p>\n
Uuringus n\u00e4itan, et selliste korduvate j\u00e4rjestuste anal\u00fc\u00fcsimiseks sobib h\u00e4sti k-mer meetod, mis on varem v\u00e4lja t\u00f6\u00f6tatud Tartu \u00dclikooli bioinformaatikute poolt. Y-kromosoomi p\u00f5hjal arvutatud k-mer sagedusi nimetati y-merideks.<\/p>\n
Genoomi uurimise h\u00fcppeline areng<\/p>\n
Vana DNA uurimine on tihedalt seotud sekveneerimistehnoloogia arenguga. Y-mer anal\u00fc\u00fcs sai v\u00f5imalikuks alates 2007. aastast, kui turule tulid uued sekveneerimismasinad. T\u00e4naseks on vana DNA andmeid kogunenud palju rohkem.<\/p>\n
Koos kolleegidega testisime meetodit proovidel, mille Y-kromosoomi haplogrupp oli juba teada. Tulemused n\u00e4itasid, et eriti t\u00e4pselt saab m\u00e4\u00e4rata suuremaid ja vanemaid haplogruppe.<\/p>\n
Lisaks arheoloogilistele proovidele katsetasime meetodit ka rasedate naiste vereproovidel (NIPT-testid). Nendes proovides on peamiselt ema DNA, kuid leidub ka v\u00e4ikeses koguses loote DNA-d.<\/p>\n
Kuna loote DNA hulk on v\u00e4ike ja killustunud, on tavap\u00e4raste meetoditega raske midagi kindlat \u00f6elda, eriti poisslapse isaliini kohta. Uuring n\u00e4itas, et y-mer meetod suudab ka sellisest andmestikust vajaliku info k\u00e4tte saada.<\/p>\n
Edasised plaanid<\/p>\n
Edaspidi plaanivad teadlased arendada sarnaseid mudeleid ka teiste kromosoomide jaoks. Samuti soovitakse luua lahendus, kus Y-kromosoomi haplogrupp m\u00e4\u00e4ratakse juba DNA sekveneerimise k\u00e4igus, mitte hiljem andmeid anal\u00fc\u00fcsides.<\/p>\n
Uus meetod vajab veel tutvustamist, et ka teised teadlased saaksid seda oma t\u00f6\u00f6s kasutada.<\/p>\n
Uuring avaldati ajakirjas Genome Biology<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Muistse DNA p\u00f5hjal saab uurida rahvaste kujunemist, kuid meeste isaliini m\u00e4\u00e4ramine on seni olnud keeruline, sest proovid on…\n","protected":false},"author":2,"featured_media":149790,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_share_on_mastodon":"0"},"categories":[80],"tags":[70583,26,27,8855,37,33,35,34,36,31,32,21,28,29,95,19,70586,25,70582,70585,2424,70584,23,24,22,20,11354,30,92,93,94],"class_list":["post-149789","post","type-post","status-publish","format-standard","has-post-thumbnail","category-maailm","tag-bioinformaatika","tag-breaking-news","tag-breakingnews","tag-dna","tag-ee","tag-eesti","tag-eesti-keel","tag-estonia","tag-estonian","tag-featured-news","tag-featurednews","tag-headlines","tag-latest-news","tag-latestnews","tag-maailm","tag-news","tag-pcr-meetod","tag-populaarseimad-lood","tag-sekveneerimine","tag-tarmo-puurand","tag-tartu-ulikool","tag-toomas-kivisild","tag-top-stories","tag-topstories","tag-uldised-uudised","tag-uudised","tag-vana-dna","tag-viimased-uudised","tag-world","tag-world-news","tag-worldnews"],"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ee\/116374576115840376","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/posts\/149789","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/comments?post=149789"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/posts\/149789\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/media\/149790"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/media?parent=149789"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/categories?post=149789"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/tags?post=149789"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}