Bilim insanlar\u0131, ya\u015flanm\u0131\u015f h\u00fccreleri k\u0131smen yeniden programlayarak gen\u00e7le\u015ftirmeyi hedefleyen bir y\u00f6ntemi ilk kez insanlarda test etmeye haz\u0131rlan\u0131yor. Y\u00f6ntemin glokom hastalar\u0131nda g\u00f6rme kayb\u0131n\u0131 geri \u00e7evirebilece\u011fi ve ileride organ yenilenmesinde kullan\u0131labilece\u011fi d\u00fc\u015f\u00fcn\u00fcl\u00fcyor<\/p>\n\n\n\n
Massachusetts’teki Whitehead Enstit\u00fcs\u00fc’nden genetik bilimci Yuancheng Ryan Lu ve ekibi, ya\u015flanm\u0131\u015f retina sinir h\u00fccrelerini gen\u00e7le\u015ftirmeye y\u00f6nelik \u00e7al\u0131\u015fmalar\u0131 kapsam\u0131nda g\u00f6zlerde yeni h\u00fccre b\u00fcy\u00fcmesi ve yeniden yap\u0131lanma belirtileri g\u00f6zlemlediklerini a\u00e7\u0131klad\u0131. \u00dc\u00e7 y\u0131ll\u0131k ba\u015far\u0131s\u0131z denemelerin ard\u0131ndan \u00fc\u00e7 gen kullan\u0131larak yap\u0131lan son uygulaman\u0131n, glokoma ba\u011fl\u0131 g\u00f6rme kayb\u0131n\u0131n geri \u00e7evrilmesine y\u00f6nelik umut verici sonu\u00e7lar verdi\u011fi belirtildi. Ara\u015ft\u0131rmac\u0131lar, bulgular\u0131n do\u011frulanmas\u0131 halinde y\u00f6ntemin ya\u015fa ba\u011fl\u0131 g\u00f6rme kayb\u0131 ve baz\u0131 organ hasarlar\u0131n\u0131n tedavisinde kullan\u0131labilece\u011fini ifade ediyor.<\/p>\n\n\n\n
Scientific American’\u0131n haberine g\u00f6re; Lu ve ekibi, h\u00fccreleri k\u0131smen daha gen\u00e7 bir duruma \u201cyeniden programlamaya\u201d \u00e7al\u0131\u015fan birka\u00e7 ekipten biriydi. Aradan ge\u00e7en yedi yo\u011fun y\u0131l\u0131n ard\u0131ndan, onun ke\u015ffi bu y\u0131l ba\u015flamas\u0131 planlanan bir klinik \u00e7al\u0131\u015fman\u0131n temelini olu\u015fturuyor. Bu, akademi ve end\u00fcstriden ara\u015ft\u0131rmac\u0131lar\u0131n yan\u0131 s\u0131ra milyarlarca dolarl\u0131k \u00f6zel yat\u0131r\u0131m\u0131n ve Silikon Vadisi elitlerinin dikkatini \u00e7eken h\u0131zla b\u00fcy\u00fcyen bir alan i\u00e7in kritik bir test olacak. Deneme \u015fu temel soruya yan\u0131t arayacak: ya\u015fl\u0131 h\u00fccreler g\u00fcvenli bir \u015fekilde yeniden gen\u00e7le\u015ftirilebilir mi?<\/p>\n\n\n\n
Baz\u0131lar\u0131na g\u00f6re bu sorunun yan\u0131t\u0131, ya\u015flanma kavram\u0131n\u0131 k\u00f6kten de\u011fi\u015ftirebilir. Ya\u015fl\u0131 organlar\u0131 gen\u00e7le\u015ftirme yolu a\u00e7abilir. Hatta en u\u00e7 ve iyimser yorumuyla t\u00fcm insan v\u00fccudunu. K\u0131smi yeniden programlama, 20 y\u0131l \u00f6nce yeti\u015fkin h\u00fccrelerin embriyonik k\u00f6k h\u00fccre benzeri bir duruma d\u00f6nd\u00fcr\u00fclebilece\u011fini g\u00f6steren temel ke\u015ffin de yeni bir sayfas\u0131n\u0131 a\u00e7may\u0131 vaat ediyor.Ancak riskler de en az umutlar kadar b\u00fcy\u00fck: Bir h\u00fccreyi k\u00f6k h\u00fccre benzeri duruma fazla yakla\u015ft\u0131rmak, onun i\u015flevini kaybetmesine ve hatta kanserle\u015fmesine yol a\u00e7abilir. Minnesota\u2019daki Mayo Clinic\u2019ten ya\u015flanma ara\u015ft\u0131rmac\u0131s\u0131 Tamir Chandra \u201cH\u00fccreler kimliklerini kaybettiklerinde bunun baz\u0131 tehlikeleri oldu\u011funu biliyoruz” diyor.<\/p>\n\n\n\n
Gen\u00e7le\u015ftirme fakt\u00f6rleri<\/p>\n\n\n\n
2006 y\u0131l\u0131nda, Kyoto \u00dcniversitesi\u2019nde \u00e7al\u0131\u015fan k\u00f6k h\u00fccre biyolo\u011fu Shinya Yamanaka ve meslekta\u015flar\u0131, \u201cYamanaka fakt\u00f6rleri\u201d olarak adland\u0131r\u0131lan d\u00f6rt transkripsiyon fakt\u00f6r\u00fcn\u00fcn yeti\u015fkin bir h\u00fccreyi embriyonik k\u00f6k h\u00fccre benzeri bir ind\u00fcklenmi\u015f pluripotent k\u00f6k (iPS) h\u00fccresine d\u00f6n\u00fc\u015ft\u00fcrebildi\u011fini ke\u015ffetti. Bu bulu\u015f, iPS h\u00fccrelerinden belirli h\u00fccre tipleri \u00fcretilip hastalara nakledilmesine dayanan k\u00f6k h\u00fccre tedavileri i\u00e7in b\u00fcy\u00fck bir d\u00f6n\u00fcm noktas\u0131 olarak g\u00f6r\u00fcld\u00fc. \u015eubat ay\u0131nda Japonya\u2019daki d\u00fczenleyiciler, \u015fiddetli kalp yetmezli\u011fi ve Parkinson hastal\u0131\u011f\u0131 i\u00e7in ilk iPS h\u00fccre temelli tedavileri onaylad\u0131.<\/p>\n\n\n\n
Ancak baz\u0131 ara\u015ft\u0131rmac\u0131lar Yamanaka fakt\u00f6rlerinin ba\u015fka bir ama\u00e7la kullan\u0131labilece\u011fini d\u00fc\u015f\u00fcnd\u00fc. 2010 y\u0131l\u0131nda, \u015fu anda Kazakistan\u2019daki Nazarbayev \u00dcniversitesi\u2019nde kromatin biyolo\u011fu olan Prim Singh ve meslekta\u015f\u0131 Fred Zacouto, ara\u015ft\u0131rmac\u0131lar\u0131n bu fakt\u00f6rleri k\u0131sa s\u00fcreli\u011fine aktive edip h\u00fccreler tamamen yeniden programlanmadan \u00f6nce kapatabileceklerini \u00f6nerdi. B\u00f6ylece h\u00fccreler kimliklerini kaybetmeden gen\u00e7le\u015febilirdi.<\/p>\n\n\n\n
Singh\u2019e g\u00f6re bu fikir o d\u00f6nemde kabul edilmesi zor bir fikirdi; \u00e7\u00fcnk\u00fc ara\u015ft\u0131rmalar\u0131n \u00e7o\u011fu iPS h\u00fccrelerine odaklanm\u0131\u015ft\u0131, gen\u00e7le\u015ftirmeye de\u011fil.2016 y\u0131l\u0131nda yay\u0131mlanan bir ba\u015fka \u00e7al\u0131\u015fma, bu yeni alan\u0131 daha g\u00f6r\u00fcn\u00fcr hale getirdi. La Jolla\u2019daki Salk Enstit\u00fcs\u00fc\u2019nde \u00e7al\u0131\u015fan k\u00f6k h\u00fccre biyolo\u011fu Juan Carlos Izpis\u00faa Belmonte ve ekibi, Yamanaka fakt\u00f6rlerini farelerde aral\u0131kl\u0131 olarak a\u00e7\u0131p kapatt\u0131klar\u0131n\u0131 bildirdi. Bu d\u00f6ng\u00fcsel aktivasyon, erken ya\u015flanma hastal\u0131\u011f\u0131 (progeria) ta\u015f\u0131yan farelerin ya\u015fam s\u00fcresini uzatt\u0131. Normal ya\u015fl\u0131 farelerde ise kas ve pankreas dokular\u0131n\u0131n yenilenmesini art\u0131rd\u0131.<\/p>\n\n\n\n
Sonraki y\u0131llarda k\u0131smi yeniden programlama \u00e7al\u0131\u015fmalar\u0131 h\u0131z kazand\u0131. Bilim insanlar\u0131 bu fakt\u00f6rleri cilt h\u00fccrelerini gen\u00e7le\u015ftirmek, yara izini azaltmak, kas yenilenmesini art\u0131rmak ve kalp h\u00fccrelerinin hasar sonras\u0131 yeniden b\u00fcy\u00fcmesini sa\u011flamak i\u00e7in kulland\u0131. Bir \u00e7al\u0131\u015fma, ya\u015fl\u0131 farelerin beyinlerinde bu fakt\u00f6rlerin haf\u0131za testlerindeki performans\u0131 art\u0131rabilece\u011fini bile \u00f6ne s\u00fcrd\u00fc.<\/p>\n\n\n\n
Yamanaka fakt\u00f6rleri ve risklerFarkl\u0131 ekipler Yamanaka fakt\u00f6rlerini daha g\u00fcvenli hale getirmeye \u00e7al\u0131\u015ft\u0131. Baz\u0131lar\u0131 genleri d\u00f6ng\u00fcsel olarak a\u00e7\u0131p kapat\u0131rken, baz\u0131lar\u0131 sadece k\u0131sa s\u00fcreli etkinle\u015ftirme yoluna gitti. Ama\u00e7, h\u00fccrelerin tamamen k\u00f6k h\u00fccre haline gelmesini \u00f6nlemekti. Yakla\u015f\u0131mlar farelerde g\u00fcvenli g\u00f6r\u00fcnse de, h\u00fccrelerin bilinmeyen bir potansiyele sahip olmas\u0131 endi\u015feleri s\u00fcrd\u00fc.Shift Bioscience CEO\u2019su Daniel Ives bu durumu \u015f\u00f6yle \u00f6zetliyor: \u201cBir dinozoru \u00e7ok iyi e\u011fitseniz bile evcil hayvan yapman\u0131z iyi bir fikir de\u011fildir\u201dLu ve di\u011ferleri, y\u00fcksek kanser riski nedeniyle c-Myc adl\u0131 fakt\u00f6r\u00fc sistemden \u00e7\u0131karmay\u0131 tercih etti. San Diego merkezli Rejuvenate Bio \u015firketinden Noah Davidsohn\u2019un y\u00fcr\u00fctt\u00fc\u011f\u00fc dikkat \u00e7ekici bir \u00e7al\u0131\u015fmada, \u00fc\u00e7 Yamanaka fakt\u00f6r\u00fc ya\u015fl\u0131 farelerin t\u00fcm v\u00fccuduna enjekte edildi. Davidsohn \u201cFarelere enjekte ettik ve a\u00e7\u0131k\u00e7as\u0131 \u00f6lmelerini bekliyorduk\u201d diyor.Ancak aylar ge\u00e7mesine ra\u011fmen t\u00fcm\u00f6r olu\u015fmad\u0131. Bunun yerine sa\u011fl\u0131k g\u00f6stergeleri iyile\u015fti ve fareler daha uzun ya\u015fad\u0131. Yine de bu erken bir \u00e7al\u0131\u015fmayd\u0131. Irvine\u2019daki California \u00dcniversitesi\u2019nden Vittorio Sebastiano, c-Myc\u2019in \u00e7\u0131kar\u0131lmas\u0131n\u0131n baz\u0131 i\u015flevleri etkileyebilece\u011fi konusunda temkinli.<\/p>\n\n\n\n
Rekor yat\u0131r\u0131m 2020 y\u0131l\u0131nda Los Altos Hills\u2019te bir grup ara\u015ft\u0131rmac\u0131, internet giri\u015fimcisi Yuri Milner ile k\u0131smi yeniden programlaman\u0131n gelece\u011fini tart\u0131\u015fmak \u00fczere bir araya geldi. Harvard T\u0131p Fak\u00fcltesi\u2019nden Vadim Gladyshev toplant\u0131y\u0131 \u201c\u00e7ok b\u00fcy\u00fck bir heyecan vard\u0131, b\u00fcy\u00fck bir \u015fey hissi\u201d s\u00f6zleriyle anlat\u0131yor.Bu toplant\u0131, Milner\u2019\u0131n da dahil oldu\u011fu yat\u0131r\u0131mc\u0131larla birlikte Altos Labs adl\u0131 \u015firketin kurulmas\u0131na yol a\u00e7t\u0131. \u015eirket 2022\u2019de 3 milyar dolarl\u0131k rekor finansmanla faaliyete ge\u00e7ti. Bu geli\u015fme, sekt\u00f6re b\u00fcy\u00fck bir yat\u0131r\u0131m dalgas\u0131 ba\u015flatt\u0131.OpenAI CEO\u2019su Sam Altman, Retro Biosciences adl\u0131 ya\u015flanma \u015firketine yat\u0131r\u0131m yapt\u0131. Coinbase CEO\u2019su Brian Armstrong ise NewLimit adl\u0131 ba\u015fka bir k\u0131smi yeniden programlama \u015firketinin kurulmas\u0131na katk\u0131da bulundu.Ancak ilk insan denemelerinin yap\u0131laca\u011f\u0131 \u015firket Life Biosciences oldu. \u015eirket, \u00fc\u00e7 Yamanaka fakt\u00f6r\u00fcn\u00fc (c-Myc hari\u00e7) glokom nedeniyle optik sinir hasar\u0131 olan hastalar\u0131n g\u00f6zlerine viral bir ta\u015f\u0131y\u0131c\u0131yla iletmeyi hedefliyor.<\/p>\n\n\n\n
\u0130lk klinik deneme <\/p>\n\n\n\n
\u015eirketin bilim direkt\u00f6r\u00fc Sharon Rosenzweig-Lipson, s\u00fcrecin yava\u015f ilerleyece\u011fini s\u00f6yl\u00fcyor. \u0130lk a\u015famada 12 glokom hastas\u0131 ve ard\u0131ndan NAION adl\u0131 akut optik sinir hasar\u0131 ya\u015fayan 6 hasta tedavi edilecek. Genler, kat\u0131l\u0131mc\u0131lar\u0131n belirli bir antibiyotik almas\u0131yla a\u00e7\u0131lan bir genetik anahtar ile kontrol edilecek. Maymun \u00e7al\u0131\u015fmalar\u0131nda kanser veya ciddi yan etki g\u00f6r\u00fclmedi\u011fi belirtiliyor ve kat\u0131l\u0131mc\u0131lar en az be\u015f y\u0131l izlenecek.<\/p>\n\n\n\n
Etki tart\u0131\u015fmas\u0131<\/p>\n\n\n\n
Baz\u0131 bilim insanlar\u0131 temkinli. Avustralya G\u00f6z Ara\u015ft\u0131rma Merkezi\u2019nden Pete Williams, bu ilk denemede etkinin anla\u015f\u0131lmas\u0131n\u0131n zor olaca\u011f\u0131n\u0131 s\u00f6yl\u00fcyor. Sebastiano ise bunun b\u00fcy\u00fck bir ilerleme olaca\u011f\u0131n\u0131 d\u00fc\u015f\u00fcn\u00fcyor.Williams\u2019a g\u00f6re sorunlardan biri, \u201cgen\u00e7le\u015fme\u201d kavram\u0131n\u0131n ne anlama geldi\u011fi. Williams \u201cE\u011fer ya\u015fl\u0131 bir insan\u0131 daha g\u00fc\u00e7l\u00fc hale getirirseniz bu onu gen\u00e7 yapmaz\u201d diyorSebastiano ise bunun bir tan\u0131m meselesi oldu\u011funu savunuyor: \u201c\u00d6nemli olan h\u00fccrelerin ya\u015flanmaya ba\u011fl\u0131 i\u015flev kayb\u0131n\u0131 g\u00fcvenli \u015fekilde tersine \u00e7evirebilmek\u201d<\/p>\n\n\n\n
Epigenetik mekanizma<\/p>\n\n\n\n
K\u0131smi yeniden programlama, ya\u015flanman\u0131n yaln\u0131zca DNA hasar\u0131ndan de\u011fil, epigenomdaki de\u011fi\u015fimlerden de kaynakland\u0131\u011f\u0131 fikrine dayan\u0131yor. Epigenom, genlerin nas\u0131l \u00e7al\u0131\u015ft\u0131\u011f\u0131n\u0131 etkileyen kimyasal i\u015faretlerden olu\u015fuyor ve ya\u015fla birlikte de\u011fi\u015fiyor.Ara\u015ft\u0131rmalar, Yamanaka fakt\u00f6rlerinin bu epigenetik i\u015faretleri geri \u00e7evirebildi\u011fini g\u00f6sterdi. Lu ve Sinclair\u2019in ekibi, retinal sinir h\u00fccrelerinde bu s\u00fcrecin DNA \u00fczerindeki metil gruplar\u0131n\u0131 kald\u0131ran enzimlere ba\u011fl\u0131 oldu\u011funu buldu.<\/p>\n\n\n\n
Alternatif yakla\u015f\u0131mlar<\/p>\n\n\n\n
T\u00fcm ara\u015ft\u0131rmac\u0131lar Yamanaka fakt\u00f6rlerine ba\u011fl\u0131 de\u011fil. NewLimit ve Shift Biosciences gibi \u015firketler farkl\u0131 gen setleri ar\u0131yor. Gladyshev\u2019in laboratuvar\u0131 ise kimyasal y\u00f6ntemlerle yeniden programlama yap\u0131yor.Gladyshev\u2019e g\u00f6re tek bir yol yok: \u201cS\u00fcre\u00e7 tam olarak anla\u015f\u0131lm\u0131\u015f de\u011fil\u201d<\/p>\n\n\n\n
Dengeyi bulmak<\/p>\n\n\n\n
Ara\u015ft\u0131rmalar, farkl\u0131 h\u00fccre tiplerinin yeniden programlamaya farkl\u0131 tepkiler verdi\u011fini g\u00f6steriyor. Almanya\u2019daki TRON Enstit\u00fcs\u00fc\u2019nden Johnny Kim, yanl\u0131\u015f dozun kanser riskini art\u0131rabilece\u011fini s\u00f6yl\u00fcyor.Baz\u0131 ara\u015ft\u0131rmac\u0131lar hedefe y\u00f6nelik tedavilerin daha g\u00fcvenli olaca\u011f\u0131n\u0131 d\u00fc\u015f\u00fcn\u00fcyor. Sevilla \u00dcniversitesi\u2019nden A\u00edda Platero Luengo, beyindeki astroglia h\u00fccrelerinin gen\u00e7le\u015ftirilmesinin inflamasyonu azaltabilece\u011fini ve genel beyin sa\u011fl\u0131\u011f\u0131n\u0131 iyile\u015ftirebilece\u011fini s\u00f6yl\u00fcyor.<\/p>\n\n\n\n
Sonu\u00e7 ve belirsizlik<\/p>\n\n\n\n
Gladyshev, gen\u00e7 organ transplantlar\u0131n\u0131n bile ya\u015flanmay\u0131 geri \u00e7evirmedi\u011fini, \u00e7\u00fcnk\u00fc v\u00fccudun organlar \u00fczerinde g\u00fc\u00e7l\u00fc bir etkisi oldu\u011funu s\u00f6yl\u00fcyor. Yine de y\u00f6ntemin b\u00fcy\u00fck potansiyel ta\u015f\u0131d\u0131\u011f\u0131n\u0131 kabul ediyor. Lu ise daha iyimser. Ke\u015ffinin klinik a\u015famaya ta\u015f\u0131nmas\u0131n\u0131 \u201cba\u011f\u0131ml\u0131l\u0131k yapan\u201d bir s\u00fcre\u00e7 olarak tan\u0131ml\u0131yor. \u201cBunu insanlara tedavi etmek i\u00e7in klini\u011fe ta\u015f\u0131mak kariyerde \u00e7ok nadir bir \u015fey\u201d diyor.<\/p>\n\n\n\n
Kaynak: https:\/\/gazeteoksijen.com\/saglik\/hucresel-genclestirme-yontemi-insanlarda-test-edilmeye-hazirlaniyor-272175<\/p>\n\n\n\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
Bilim insanlar\u0131, ya\u015flanm\u0131\u015f h\u00fccreleri k\u0131smen yeniden programlayarak gen\u00e7le\u015ftirmeyi hedefleyen bir y\u00f6ntemi ilk kez insanlarda test etmeye haz\u0131rlan\u0131yor. Y\u00f6ntemin glokom hastalar\u0131nda g\u00f6rme kayb\u0131n\u0131 geri \u00e7evirebilece\u011fi ve ileride organ yenilenmesinde kullan\u0131labilece\u011fi d\u00fc\u015f\u00fcn\u00fcl\u00fcyor Massachusetts’teki Whitehead Enstit\u00fcs\u00fc’nden genetik bilimci Yuancheng Ryan Lu ve ekibi, ya\u015flanm\u0131\u015f retina sinir h\u00fccrelerini gen\u00e7le\u015ftirmeye y\u00f6nelik \u00e7al\u0131\u015fmalar\u0131 kapsam\u0131nda g\u00f6zlerde yeni h\u00fccre b\u00fcy\u00fcmesi ve yeniden yap\u0131lanma […]<\/p>\n","protected":false},"author":2,"featured_media":5414,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[3],"tags":[],"class_list":["post-5413","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-saglik"],"jetpack_featured_media_url":"https:\/\/gundexia.com\/wp-content\/uploads\/2026\/04\/1000108466.jpg","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/gundexia.com\/index.php?rest_route=\/wp\/v2\/posts\/5413","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gundexia.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gundexia.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gundexia.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/gundexia.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=5413"}],"version-history":[{"count":2,"href":"https:\/\/gundexia.com\/index.php?rest_route=\/wp\/v2\/posts\/5413\/revisions"}],"predecessor-version":[{"id":5417,"href":"https:\/\/gundexia.com\/index.php?rest_route=\/wp\/v2\/posts\/5413\/revisions\/5417"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/gundexia.com\/index.php?rest_route=\/wp\/v2\/media\/5414"}],"wp:attachment":[{"href":"https:\/\/gundexia.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5413"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gundexia.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5413"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gundexia.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5413"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}