Nazariyai khromosomii irsiyat

Nazariyai khromosomii irsiyat, nazariyai az nasl ba nasl guzash- tani alomatho ba vositai khromoso­ma, ki avvali asri 20 ba vujud omad Bi­no ba farziyae, ki soli 1902 olimi amerikoi U. Setton va olimi nemis T. Boveri peshnihod kardand, genho dar khromosomaho joi muayyan dorand. Minbad Nazariyai khromosomii irsiyat dar asarhoi genetikhoi amerikoi T. X. Morgav, K. Brijes va digaron asosnok karda shud. Muqarrar gardid, ki genhoi yak khro­mosoma yak guruhi payvastro tashkil namuda, boyad yakjoya meros girifta shavand. Miqdori guruhhoi payvast ba miqdori jufti khromosomaho ba­robar buda, baroi har yak namudi organizmho doimi ast (nig. Kariotip). Alomathoi payvasti genho niz yakjoya meros girifta meshavand. Az in ru istifodai qonuni kombinasiyai bevositai alomatho (nig. Qonunhoi Mendel) mahdudtar meshavad, yane alomathoi genhoyashon dar khromosomahoi gunogun (gayri gomologi) joygirshuda, alohida- alohida meros girifta meshavand. Hodisai payvas­ti nopurrai genhoshro Morgan va hamkoroni u mufassal tadqiq kardand va dar in zamina dar khromosoma pay dar pay joygir shudani genhoro asosnok namudand. Ba aqidai Mor­gan genhoi payvastshudai khromosomahoi gomologi, ki dar volidayn dar namudi  va   hangomi meyoz dar shakli geterozi­segoti →     joi khudro ivaz karda metavonand. Dar natija barobari ga­metahoi AV va ab gametahoi Ab va aV hosil meshavand. Sababi in hamin ast, ki aloqai khromosomahoi gomologi dar mobayni genhoi  .   kanda shuda, sipas nuqhoi

A     V

onho dar namudi ͟͞    X ͟͞       boya n ayv ast meshavavd.

a      b

Dar haqiqat vujud doshtani in prosessro, ki krossingover nom dorad, soli 1933 olimi nemis K. Shtern va olimoni amerikoi X. Kreytov, B. Mak-Klintok isbot kardand. Nisbati basomadi krosossingover va masofai bayni genhoi payvast baroi tahiyai haritai genetikii khromosomaho istifoda meshavad.

Alhol masalai homili universali budani molekulahoi kislotai de- zoksiribonukleat mavridi tadqiqi mufassal qaror giriftaast va inki- shofi minbadai Nazariyai khromosomii irsiyat mahz ba hamin samt idoma dorad. Nazariyai khromosomii irsiyat, ki qonuniyati az nasl ba nasl guzashta- ni alomathoi irsiro tadqiq menamoyad, dar ravnaqu rivoji ilm va amaliyai khojagii qishloq ahamiyati kalon dorad. Nazariyai khromosomii irsiyat dar dasti seleksionerho vositai tavonoe meboshad va mahz dar asosi on namudu navhoi dilkhohi hayvonot va nabotot ba vujud ovarda meshavand. Donistani qonuniyathoi joygirshavii khromosomaho yake az asoshoi tadqiqi bemorihoi irsii odam meboshad.

Ad.: Morgan T. G., Iabr. raboti po genetike, M.—L., 1937; Lobashev M. E. Genetika, L., 1967.